Patent Publication Number: US-2023136614-A1

Title: Extended range of fuel cell machine

Description:
TECHNICAL FIELD 
     The present disclosure relates to a machine powered by a fuel cell. More specifically, the present disclosure relates to extending ranges of fuel cell machines, such as mining trucks. 
     BACKGROUND 
     Machines, such as mining trucks, loaders, dozers, compaction machines, or other construction or mining equipment, are often powered by any variety of fuel, including fuel cells that operate using hydrogen or hydrogen containing (e.g., natural gas) fuel. Machines powered by fuel cells are used for building, construction, mining and other activities. For example, mining trucks are often used for hauling mined materials from mining sites. It is desirable to power these types of machines using alternative fuels, such as hydrogen powering fuel cells. Fuel cell machines, for example, may benefit from reduced emissions of carbon (e.g., carbon dioxide), particulates (e.g., diesel soot), nitrous oxide (e.g., NOx), and/or organic (e.g., volatile organic compounds (VOC)) emissions relative to traditional fuel (e.g., diesel, gasoline, etc.) powered machines. 
     While fuel cell powered machinery may provide various improvements, such as environmental advantages, fuel cell powered machinery may also suffer from some challenges, such as low energy density of hydrogen fuel, low range of fuel cell machines between refueling, and long refueling times. It is, therefore, desirable to increase the operating time of fuel cell machines between refueling. 
     One mechanism for operating a fuel cell system is described in U.S. Pat. No. 7,224,524 (hereinafter referred to as “the &#39;524 reference”). The &#39;524 reference describes switching from a primary power source to a secondary power source, such as a fuel cell. The &#39;524 reference describes procedures associated with the switchover to a fuel cell power source. However, the systems and methods described in the &#39;524 reference does not pertain to the operation or control of a fuel cell powered machine. Thus, the disclosure of the &#39;524 reference does not describe how to extend the range of a fuel cell machine. 
     Examples of the present disclosure are directed toward overcoming one or more of the deficiencies noted above. 
     SUMMARY 
     In an aspect of the present disclosure, a machine includes a motor, a fuel tank configured to hold fuel, a fuel tank controller configured to report an amount of fuel in the fuel tank, a fuel cell configured to power the motor using fuel held in the fuel tank, a battery configured to power the motor, a battery controller configured to report an amount of charge in the battery, and an engine control module (ECM). The ECM is configured to start performing a task, the task including operating the motor using one or both of the fuel cell and the battery. The ECM is further configured to receive, from the fuel tank controller, a first indication that the fuel has been depleted and continue, based at least in part on the first indication that the fuel has been depleted, performing the task using the battery. The ECM is still further configured to receive from the battery controller a second indication that the battery is within a threshold level of being depleted and cause, based at least in part on the second indication that the battery being within the threshold level of being depleted, the task to be halted. 
     In another aspect of the present disclosure, a method of operating a machine includes performing, by the machine, a task using energy from one or both of a fuel cell and a battery, determining that a fuel cell fuel for operating the fuel cell has been depleted, and continuing, based at least in part on the fuel being depleted, performing the task using energy from the battery. The method further includes determining that the battery is within a threshold level of being depleted and moving, based at least in part on the battery being within the threshold level of being depleted, the machine to a refueling/charging station. 
     In yet another aspect of the present disclosure, a controller of a machine includes one or more processors and one or more computer-readable media storing computer-executable instructions that, when executed by the one or more processors, cause the one or more processors to receive, from a fuel tank controller, a first indication of a remaining amount of fuel cell fuel in a fuel tank and determine a first amount of energy associated with the fuel cell fuel based at least in part on the remaining amount of fuel cell fuel in the fuel tank. The computer-executable instructions that, when executed by the one or more processors, further cause the one or more processors to receive, from a battery controller, a second indication of a remaining amount of charge in a battery and determine a second amount of energy associated with the battery based at least in part on the remaining amount of charge in the battery. The computer-executable instructions that, when executed by the one or more processors, still further cause the one or more processors to determine that a total energy available to operate the machine based at least in part on the second amount of energy and cause to display the total energy available to operate the machine on an energy gauge. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG.  1    is a schematic illustration of an example fuel cell machine, in accordance with examples of the disclosure. 
         FIG.  2    is a schematic illustration of a worksite with the fuel cell machine depicted in  FIG.  1   , according to examples of the disclosure. 
         FIG.  3    is a schematic illustration depicting an example control environment of the fuel cell machine of  FIG.  1   , according to examples of the disclosure. 
         FIG.  4    is a flow diagram depicting an example method for operating the fuel cell machine of  FIG.  1   , according to examples of the disclosure. 
         FIG.  5    is a flow diagram depicting an example method for displaying a level of energy available for operating the fuel cell machine of  FIG.  1   , according to examples of the disclosure. 
         FIG.  6    is a flow diagram depicting an example method for performing a task using the fuel cell machine of  FIG.  1   , according to examples of the disclosure. 
         FIG.  7    is a flow diagram depicting an example method for operating the fuel cell machine of  FIG.  1   , according to examples of the disclosure. 
         FIG.  8    is a block diagram of an example engine control module (ECM) that may operate the fuel cell machine of  FIG.  1   , according to examples of the disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. 
       FIG.  1    is a schematic illustration of an example fuel cell machine  100 , in accordance with examples of the disclosure. The fuel cell machine  100 , although depicted as a mining truck type of machine, may be any suitable machine, such as any type of loader, dozer, dump truck, skid loader, excavator, compaction machine, backhoe, combine, crane, drilling equipment, tank, trencher, tractor, any suitable stationary machine, any variety of generator, locomotive, marine engines, combinations thereof, or the like. The fuel cell machine  100  is configured for propulsion using hydrogen and/or hydrogen containing compounds, such as various hydrocarbons (methane, ethane, propane, butane, pentane, hexane, combinations thereof, or the like), compressed natural gas (CNG), natural gas, liquified natural gas (LNG), combinations thereof, or the like. 
     The fuel cell machine  100  is illustrated as a mining truck, which is used, for example, for moving mined materials, heavy construction materials, and/or equipment, and/or for road construction, building construction, other mining, paving and/or construction applications. For example, the fuel cell machine  100  is used in situations where materials, such as mineral ores, loose stone, gravel, soil, sand, concrete, and/or other materials of a worksite need to be transported over a surface  102  at the worksite. As discussed herein, the fuel cell machine  100  may also be in the form of a dozer, where the fuel cell machine  100  is used to redistribute and/or move material on the surface  102 . Further still, the fuel cell machine  100  may be in the form of a compaction machine that can traverse the surface  102  and impart vibrational forces to compact the surface  102 . Such a compaction machine includes drums, which may vibrate to impart energy to the surface  102  for compaction. For example, a fuel cell compaction machine is configured to compact freshly deposited asphalt and/or other materials disposed on and/or associated with the surface  102 , such as to build a road or parking lot. It should be understood that the fuel cell machine  100  can be in the form of any other type of suitable construction, mining, farming, military, and/or transportation machine. In the interest of brevity, without individually discussing every type of construction and/or mining machine, it should be understood that the fuel cell drive mechanisms, as described herein, are configured for use in a wide variety of fuel cell powered machines  100 . 
     As shown in  FIG.  1   , the fuel cell machine  100  includes a frame  104  and wheels  106 . The wheels  106  are mechanically coupled to a drive train (not shown) to propel the fuel cell machine  100 . When the wheels  106  of the fuel cell machine  100  are caused to rotate, the fuel cell machine  100  traverses the surface  102 . Although illustrated in  FIG.  1    as having a hub with a rubber tire, in other examples, the wheels  106  may instead be in the form of drums, chain drives, combinations thereof, or the like. 
     The frame  104  of the fuel cell machine  100  is constructed from any suitable materials, such as iron, steel, aluminum, other metals, ceramics, plastics, the combination thereof, or the like. The frame  104  is of a unibody construction in some cases, and in other cases, is constructed by joining two or more separate body pieces. Parts of the frame  104  are joined by any suitable variety of mechanisms, including, for example, welding, bolts, screws, other fasteners, epoxy, combinations thereof, or the like. 
     The fuel cell machine  100  may include a hydraulic system  108  that move a dump box  110  or other moveable elements configured to move, lift, carry, and/or dump materials. The dump box  110  is used, for example, to pick up and carry dirt or mined ore from one location on the surface  102  to another location of the surface  102 . The dump box  110  is actuated by the hydraulic system  108 , or any other suitable mechanical system. In some cases, the hydraulic system  108  is powered by an electric motor (not shown), such as by powering hydraulic pump(s) (not shown) of the hydraulic system  108 . It should be noted that in other types of machines (e.g., machines other than a mining truck) the hydraulic system  108  may be in a different configuration than the one shown herein, may be used to operate elements other than a dump box  110 , and/or may be omitted. 
     With continued reference to  FIG.  1   , the fuel cell machine  100  also includes an operator station  112 . The operator station  112  is configured to seat an operator (not shown) therein. The operator seated in the operator station  112  interacts with various control interfaces and/or actuators within the operator station  112  to control movement of various components of the fuel cell machine  100  and/or the overall movement of the fuel cell machine  100  itself. 
     Thus, control interfaces and/or actuators within the operator station  112  allow the control of the propulsion of the fuel cell machine  100  by controlling operation of one or more motors  114 . A motor controller  116  may be controlled according to operator inputs received at the operator station  112 . The motors  114  may be powered by a battery pack or battery  118 , with a battery controller  120 , and/or a fuel cell  122 , with a fuel cell controller  124 . 
     The motors  114  may be of any suitable type, such as induction motors, permanent magnet motors, switched reluctance (SR) motors, combinations thereof, or the like. The motors  114  are of any suitable voltage, current, and/or power rating. The motors  114  when operating together are configured to propel the fuel cell machine  100  as needed for tasks that are to be performed by the fuel cell machine  100 . For example, the motors  114  may be rated for a range of about 500 volts to about 3000 volts. The motor controller  116  include one or more control electronics to control the operation of the motors  114 . In some cases, each motor  114  may be controlled by its own motor controller  116 . In other cases, all the motors of the fuel cell machine  100  may be controlled by a single motor controller  116 . The motor controller  116  may further include one or more inverters or other circuitry to control the energizing of magnetic flux generating elements (e.g., coils) of the motors  114 . The motors  114  are mechanically coupled to a variety of drive train components, such as a drive shaft and/or axles or directly to the wheels  106  to rotate the wheels  106  and propel the fuel cell machine  100 . The drivetrain includes any variety of other components including, but not limited to a differential, connector(s), constant velocity (CV) joints, etc. Although not shown here, there may be one or more motors  114  that are not used for propulsion of the fuel cell machine  100 , but rather to operate pumps and/or other auxiliary components, such as to operate the hydraulic systems  108 . 
     According to examples of the disclosure, the power to energize the motors  114  is received from the battery  118 , the fuel cell  122 , or both the battery  118  and the fuel cell  122 . In some cases, the motors  114  may operate solely from the power produced by the fuel cell  122 . In other cases, the power received from the fuel cell  122  to operate the motors  114  may be supplemented by power from the battery  118 . Fuel cells generally provide a relatively steady level of power and generally do not ramp up or ramp down significantly or quickly from a baseline level of power. As a result, when a high level of power is needed to power the motors  114 , power may be drawn from the fuel cell  122  and the battery  118  contemporaneously. According to examples of the disclosure, in some cases, the battery  118  may provide power for operating the motors  114  and/or other power consuming components (e.g., controllers, cooling systems, displays, actuators, sensors, etc.) of the fuel cell machine  100  while the fuel cell  122  does not provide power for operating the motors  114  and/or other power consuming components. In some cases, the motors  114  may be run using power from the fuel cell  122  or from a combination of the fuel cell  122  and the battery  118  until fuel for the fuel cell  122  is fully consumed. When the fuel is consumed, the fuel cell machine  100  may still be operated using power from the battery  118  until the battery  118  no longer has sufficient power to operate the fuel cell machine  100 . In this way, the range and/or the time of operation of the fuel cell machine  100  is extended beyond the range and/or time of operation of the fuel cell machine  100  according to the available fuel cell fuel available to the fuel cell machine  100 . 
     In some cases, when the fuel cell machine  100  is operated with energy from the battery  118  only, the fuel cell machine  100  may be operated in a derated mode. This derated mode may reduce the peak power consumed by the fuel cell machine  100 , such that the peak power draw by the subcomponents (e.g., motors  114 , controller, etc.) do not exceed the power rating of the battery  118 . In this way, the fuel cell machine  100  may prevent damaging and/or excessively depleting the battery  118  during its operation using energy only from the battery  118 . This derated mode may manifest in a reduced/limited speed, a reduced/limited force, or the like of actions performed by the fuel cell machine  100 . 
     The fuel cell machine  100  further includes a fuel tank  126  to store the fuel cell fuel. A fuel tank controller  128  is coupled with the fuel tank to determine and/or report the fuel level within the fuel tank  126 . The fuel tank  126  may hold hydrogen (H) to power the fuel cell  122 . In other cases, the fuel tank may hold other H containing fuels, such as compressed natural gas (CNG), liquefied petroleum gas (LPG), other gaseous fuels, other liquid fuels, other cryogenic fuels, methane, ethane, propane, butane, pentane, hexane, heptane, octane, ethene, propene, isobutene, butadiene, pentene, any suitable alkane, any suitable alkene, any suitable alkyne, any suitable cycloalkane, combinations thereof, or the like. It should also be noted that the fuel cell fuel held in the fuel tank  126  may include impurities, such as nitrogen, oxygen, argon, air, or the like. The fuel tank controller  128  may include one or more sensors, such as a pressure sensor, a hall sensor, a temperature sensor, a hygrometer, or the like, that allows the fuel tank controller to determine the amount of fuel cell fuel within the fuel tank  126 . Although the fuel tank  126  is depicted as a single canister, it should be understood that the fuel tank  126  may be of any suitable size or shape and, in some cases, there may be more than one fuel tank  126  that are separate or fluidically coupled to each other. 
     The battery  118  may be of any suitable type and capacity. For example, the battery may be a lithium ion battery, a lead-acid battery, an aluminum ion battery, a flow battery, a magnesium ion battery, a potassium ion battery, a sodium ion battery, a metal hydride battery, a nickel metal hydride battery, a cobalt metal hydride battery, a nickel-cadmium battery, a wet cell of any type, a dry cell of any type, a gel battery, combinations thereof, or the like. The battery  118  may be organized as a collection of electrochemical cells arranged to provide the voltage, current, and/or power requirements of the motors  114 . In some cases, the energy capacity of the battery  118  relative to the energy available from a full fuel tank  126  may be in the range of about 0.2 to about 1.5. In other cases, the energy capacity of the battery  118  relative to the energy available from a full fuel tank  126  may be in the range of about 0.5 to about 1. In still other cases, the energy capacity of the battery  118  relative to the energy available from a full fuel tank  126  may be in the range of about 0.7 to about 0.9. These aforementioned ratios may generally be more than what is typically used for fuel cell vehicles. It should be understood that the aforementioned ratios are examples, and the disclosure contemplates battery  118  energy capacity to fuel tank  126  energy capacity ratios in ranges outside of the aforementioned ranges. 
     The fuel cell  122  may be of any suitable type, such as a proton exchange membrane (PEM) fuel cell, a solid oxide fuel cell, an alkaline fuel cell, a solid-acid fuel cell, combinations thereof, or the like. As discussed herein, the energy output of the fuel cell  122  may be approximately similar to the energy output of the battery  118 . In this type of energy ratio of the battery  118  and the fuel cell  122 , the battery  118  can not only provide fast supplemental power to the motors  114  while the fuel cell  122  is also providing power to the motors  114 , but the battery  118  is also able to operate the fuel cell machine  100  after the fuel cell fuel in the fuel tank  126  is fully depleted. In this way, according to examples of the disclosure, the range and/or the time of operation of the fuel cell machine  100  can be extended beyond that of the fuel cell operation alone or fuel cell operation supplemented with battery power at the same time. 
     The fuel cell machine  100  includes an engine control module (ECM)  130  that controls various aspects of the fuel cell machine  100 . The ECM  130  is configured to receive battery status (e.g., state-of-charge (SOC) or other charge related metrics) from the battery controller  120 , fuel level from the fuel tank controller  128 , operator signal(s), such as an accelerator signal, based at least in part on the operator&#39;s interactions with one or more control interfaces and/or actuators of the fuel cell machine  100 . In other cases, the ECM  130  may receive control signals from a remote control system by wireless signals, received via an antenna  132 . The ECM  130  uses the operator signal(s), regardless of whether they are received from an operator in the operator station  112  or from a remote controller, to generate command signals to control various components of the fuel cell machine  100 . For example, the ECM  130  may control the motors  114  via the motor controller  116 , the fuel cell  122  via the fuel cell controller  124 , the hydraulic system  108 , and/or steering of the fuel cell machine  100  via a steering controller  134 . It should be understood that the ECM  130  may control any variety of other subsystems of the fuel cell machine  100  that are not explicitly discussed here to provide the fuel cell machine  100  with the operational capability discussed herein. 
     The ECM  130 , according to example of this disclosure, may be configured to provide an indication of remaining energy to operate the fuel cell machine  100  on an energy gauge  136 . The energy gauge  136 , according to examples of the disclosure, may be configured to display the amount of energy available to operate the fuel cell machine  100  based at least in part on the fuel cell fuel remaining in the fuel tank  126  and the amount of charge remaining in the battery  118 . In some cases, the energy gauge  136  may provide an indication of an estimated amount of time the fuel cell machine  100  can be operated and/or an estimated amount of range the fuel cell machine  100  has remaining. These estimates may be generated based on the amount of fuel cell fuel remaining in the fuel tank  126 , the amount of charge remaining in the battery  118 , the recent usage of energy by the fuel cell machine  100 , and/or an estimate of the energy expended per unit time (e.g., power requirement) of a task in which the fuel cell machine  100  is engaged. The energy gauge  136  may be configured to display, to an operator seated in the operator station  112 , the amount of energy, time, and/or range remaining for operating the fuel cell machine  100 . Additionally or alternatively, the energy gauge  136  and/or the ECM  130  may be configured to indicate, such as wirelessly via the antenna  132 , the amount of energy, time, and/or range remaining for operating the fuel cell machine  100  to a remote operating system. 
     The ECM  130  includes single or multiple microprocessors, field programmable gate arrays (FPGAs), digital signal processors (DSPs), and/or other components configured to control the fuel cell machine  100 . Numerous commercially available microprocessors can be configured to perform the functions of the ECM  130 . Various known circuits are operably connected to and/or otherwise associated with the ECM  130  and/or the other circuitry of the fuel cell machine  100 . Such circuits and/or circuit components include power supply circuitry, inverter circuitry, signal-conditioning circuitry, actuator driver circuitry, etc. The present disclosure, in any manner, is not restricted to the type of ECM  130  or the positioning depicted of the ECM  130  and/or the other components relative to the fuel cell machine  100 . The ECM  130  is configured to control the use of energy from the battery  118  and the fuel cell  122  in a manner that enhances the range of the fuel cell machine  100 . 
     The fuel cell machine  100  further includes any number of other components within the operator station  112  and/or at one or more other locations on the frame  104 . These components include, for example, one or more of a location sensor (e.g., global positioning system (GPS)), an air conditioning system, a heating system, communications systems (e.g., radio, Wi-Fi connections), collision avoidance systems, sensors, cameras, etc. These systems are powered by any suitable mechanism, such as by using a direct current (DC) power supply powered by the fuel cell  122  and/or battery  118 . 
     It should be understood that the fuel cell machine  100  as discussed herein, provides for an extended range and/or extended time of operation compared to conventional fuel cell equipment. This range enhancement is enabled by operating the fuel cell machine  100  using fuel cell fuel until all of the fuel cell fuel is depleted and then operating the fuel cell machine  100  until the battery is depleted or close to being depleted. 
       FIG.  2    is a schematic illustration of a worksite  200  with the fuel cell machine  100  depicted in  FIG.  1   , according to examples of the disclosure. The worksite  200  may have more than one fuel cell machine  100 . For example, as depicted in  FIG.  2   , the worksite  200  may include other fuel cell machines  100 , such as in the form of a mining truck, an excavator, a backhoe, a dozer, or the like. It should be understood that in some cases, the worksite  200  may include both fuel cell machines  100 , as well as conventional machines (e.g., internal combustion engine machines) or any other type of machine (e.g., battery only electric machines). 
     The worksite  200  includes a variety of different locations in which or to which the fuel cell machine  100  may be maneuvered, staged, maintained, stored, parked, supplied, and/or used to perform work, such as by operator control and/or in an automated fashion. The worksite  200  includes a refueling/charging station  202  and one or more work area  204 , where fuel cell machine(s)  100  may perform tasks. For example, as depicted here, a fuel cell machine  100  in the form of an excavator may be used to dig mineral ore, while another fuel cell machine  100  in the form of a mining truck may be loaded with the mineral ore for hauling. Other tasks may involve other work activities, such as digging dirt, distributing asphalt, redistributing gravel, harvesting wheat, or the like. Although the work area  204  is depicted as an open pit mine, it should be understood that the work area  204  may be any suitable location in any suitable application, such as construction, mining, farming, transportation, or the like. For example, the work area  204  may be in the form of a paving site, an industrial site, a factory floor, a building construction site, a road construction site, a quarry, a building, a city, combinations thereof, or the like. 
     The refueling/charging station  202  may allow the fuel cell machines  100  to refuel, such as by filling the fuel tank  126  with additional fuel cell fuel, such as hydrogen and/or other hydrogen containing molecules. For example, pumps (not shown) or other flow devices may be attached to the fuel tank  126  of the fuel cell machine  100  to provide the fuel tank  126  with additional fuel. The refueling/charging station  202  may also allow the fuel cell machine  100  to recharge its battery  118 . For example, charging wire(s) may be attached to the fuel cell machine  100  to provide the battery  118  with electricity to recharge. In some cases, the fuel cell machine  100  may be both recharged and refueled at the same time at the refueling/charging station  202 . In some other cases, such as when a worksite  200  does not have electrical infrastructure available, the fuel cell machine  100  may be configured to recharge the battery  118  using the fuel cell  122  while the fuel cell machine  100  is refueled. 
     The fuel cell machine  100  may be able to communicate via wireless signals  206  with an electronic device  208  configured to generate and send remote task commands to control the fuel cell machine  100 . The electronic device  208  may have control software  210  operating thereon to generate the task commands to send via the wireless signals  206 . In some cases, the electronic device  208  may be housed in a trailer or control center  212  at the worksite  200 . In other cases, the electronic device may be located remote to the worksite  200 . The fuel cell machine  100  may receive the wireless signal  206  carrying a task command via the antenna  132 . The ECM  130  may demodulate and/or decode the received wireless signal  206  to determine the task command. The ECM may then control various subsystems of the fuel cell machine  100  to perform the task indicated in the task command. It should be understood that the fuel cell machine  100  may be controlled by an operator positioned in the operator station  112  or by the electronic device  208  controlled by a remote operator  214 . The electronic device  208  may be controlled by a remote operator  214  (e.g., worksite  200  manager, construction worker, miner, farmer, paver, etc.) in some cases. 
     The electronic device  208 , with the control software  210  running thereon, may send one or more task commands to the fuel cell machine  100  to assign the fuel cell machine  100  one or more tasks. For example, the electronic device  208  may generate a mobilization command and transmit the same via the wireless signal  206 . Thus, the electronic device  208 , with the software application running thereon, may receive input from the remote operator  214 , such as via one or more human machine interface(s) (HMIs), to proceed with generating the mobilization command. The human operator  214  may provide any variety of parameters, corresponding to desired operating characteristics of the fuel cell machine  100  for the mobilization of the fuel cell machine  100 , such as destination location, speed, etc. These parameters may be encoded by the electronic device  208  into a mobilization command, or a particular task command, that is transmitted to the fuel cell machines  100  via the wireless signal  206 . 
     In some instances, the communications between the electronic device  208  and the fuel cell machines  100  may be via protocol based communications (e.g., direct Wi-Fi, Wi-Fi, the Internet, Bluetooth, etc.), and in other instances, the communications may be non-protocol-based communications (e.g., remote control). In examples of the disclosure, the worksite  200  with communications between one or more electronic devices  208  and one or more fuel cell machines  100  may result in a worksite level network, such as a local area network (LAN) or a wide-area network (WAN). Although the electronic device  208  is depicted herein as a smartphone, it should be understood that the electronic device  208  may be any suitable type of electronic device. For example, the electronic device  208  may be a computer, a mobile device, a server, a tablet computer, a notebook computer, a handheld computer, a workstation, a desktop computer, a laptop, any variety of user equipment (UE), a network appliance, an e-reader, a wearable computer, a network node, a microcontroller, a smartphone, or another computing device. The control software  210  that operates on the electronic device  208  to enable it to control the operations of the fuel cell machines  100 , such as with task commands, may be downloaded to the electronic device  208  from any suitable website, such as a commercial app downloading website, or the like. 
     The ECM  130  may receive one or more task commands from the electronic device  208  and/or local commands from an operator in the operator station  112 , and perform a corresponding task. According to examples of the disclosure, the ECM  130 , in some cases, may determine the amount of time the fuel cell machine  100  can perform the task, based at least in part on the amount of fuel cell fuel remaining in the fuel tank  126 , the amount of charge remaining in the battery  118 , and/or an estimate of the amount of energy required to perform the task. In some cases, the ECM  130  may cause the fuel cell machine  100  to perform the assigned task autonomously and continue performing the task until the total energy available, as a combined energy of the fuel cell fuel in the fuel tank  126  and the energy remaining in the battery  118 , is within a threshold of depletion. When the remaining energy available to the fuel cell machine  100  is within a threshold of depletion, the ECM  130  may indicate that the available energy is near depletion and/or autonomously return to the refueling/charging station  202  to refuel and/or recharge. 
     In some cases, the ECM  130  may repeatedly communicate with the battery controller  120  and/or the fuel cell controller  124  to repeatedly determine the level of energy available to the fuel cell machine  100  to perform a task. In the same or other cases, the ECM  130  may repeatedly provide an updated level of energy remaining to be displayed on the energy gauge  136 . For the aforementioned operation and/or energy display, the ECM  130  may determine the available energy remaining as a sum of the energy available from the fuel cell fuel remaining in the fuel tank  126  and the remaining energy available from the battery  118  after the fuel cell fuel is depleted. In some cases, in addition to or instead of displaying the energy remaining to operate the fuel cell machine  100 , the ECM  130  may cause the display, such as via the energy gauge  136 , an estimated remaining time of operation of the fuel cell machine  100 . This estimated remaining time of operation may be determined based at least in part on the total energy available for operating the fuel cell machine  100  (e.g., sum of energy available from the fuel cell fuel remaining and the remaining charge of the battery  118 ), along with an estimate of the amount of energy used per unit time to perform a task in which the fuel cell machine  100  is engaged. In some cases, the estimated remaining time of operation may be based at least in part on a distance that is to be traversed to empty a load, a remaining number of work cycles remaining to be performed, and/or any other suitable information that can be estimated based on historical average usage. In other cases, the ECM  130  may determine and display other suitable metrics of remaining usage, such as distance or range remaining and/or cycles of work remaining (e.g., number of trucks to load). 
     It will be understood that regardless of whether the fuel cell machine  100  is operated autonomously, by remote control, and/or by an operator in the operator station  112 , the time of operation between recharging and/or refueling can be increased by using all of the energy from the fuel cell fuel to operate the fuel cell machine  100  and then continue operating the fuel cell machine  100  using energy from the battery  118  until the battery  118  is nearly depleted (e.g., within a threshold level of depletion). The battery  118  may not be fully depleted, as some energy will be needed to return the fuel cell machine  100  to the refueling/charging station  202 . Thus, the systems and mechanisms discussed herein provide enhanced operation time, range, and/or task completion between visits to the refueling/charging station  202  relative to operating the fuel cell machine  100  only until the fuel cell fuel is depleted. This enhances the productivity and/or efficiency of the fuel cell machines  100  at the worksite  200 . 
       FIG.  3    is a schematic illustration depicting an example control environment  300  of the fuel cell machine  100  of  FIG.  1   , according to examples of the disclosure. As discussed herein, the ECM  130  may receive a variety of signals that it processes to enable that the fuel cell machine  100  operates to its energy capacity before returning to the refueling/charging station  202  to refuel and/or recharge. The ECM  130  may, in some examples, cause the fuel cell machine  100  to automatically move to the refueling/charging station  202  when the energy has been nearly depleted, such as within a threshold energy level of depletion. In the same or other examples, the ECM  130  may provide a repeated and/or continuous update on the level of total energy (e.g., from the fuel cell fuel and the charge remaining in the battery  118 ) remaining for operating the fuel cell machine  100 , such as via the energy gauge  136 . In yet other cases, the ECM  130  may estimate the amount of time it can perform a task based on the level of total energy available and an estimate of the energy required per unit time (e.g., power requirement) to perform the task. 
     As discussed herein, the ECM  130  may receive signals from the fuel tank controller  128  that indicate the level of fuel cell fuel in the fuel tank  126 . This indication may be in terms of any suitable physical attribute of the fuel cell fuel, such as the pressure of the fuel cell fuel within the fuel tank  126 , the weight of the fuel cell fuel, etc. The ECM  130 , regardless of the physical attribute of the fuel cell fuel received from the fuel tank controller  128 , may be configured to convert that physical attribute to a level of energy available to operate the fuel cell machine  100 . The ECM  130  may further receive an indication of an attribute of the battery  118  from the battery controller  120 , such as a state-of-charge (SOC) or any other suitable metric. The ECM  130  may determine, based at least in part on the communication from the battery controller  120 , an amount of energy available from the battery  118  to operate the fuel cell machine  100 . The ECM 130  may be able to determine the total level of energy available to operate the fuel cell machine  100  based at least in part on the energy remaining in the battery  118  and the energy remaining in the fuel tank  126 . 
     The ECM  130  may command the fuel cell controller  124  to operate the fuel cell  122  based at least in part on the amount of fuel cell fuel remaining in the fuel tank  126 . In some cases, the ECM  130  may command the fuel cell controller  124  to operate the fuel cell  122  at constant and relatively efficient manner. If the level of current generated by the fuel cell  122  exceeds that needed for operating the fuel cell machine  100 , the additional current may be used to charge the battery  118 . The ECM  130  may also command the battery controller  120  to provide current to operate the fuel cell machine  100 . In some cases, the battery  118  and the fuel cell  122  may provide electrical current contemporaneously to operate the fuel cell machine  100 , such as to operate the motors  114 . 
     In some cases, the ECM  130  may be configured to receive remote command(s) via the antenna  132 . The ECM  130  may control the fuel cell machine  100  to perform a task based at least in part on the received remote command(s). In some cases, the task may be performed autonomously by the fuel cell machine  100 , controlled by the ECM  130 . The ECM  130  may control a variety of subsystems of the fuel cell machine  100 , such as by controlling the motor controller  116  and/or the steering controller  134 . According to examples of the disclosure, the ECM  130  may control the fuel cell machine  100  to perform the task even after all of the fuel cell fuel is depleted and until all of (or most) of the battery  118  is depleted. In additional examples of the disclosure, the ECM  130  may provide an indication of remaining energy, remaining estimated operation time, or the like, of the fuel cell machine  100 , such as via the energy gauge  136  and/or by transmitting the same to the electronic device  208 . 
       FIG.  4    is a flow diagram depicting an example method  400  for operating the fuel cell machine of  FIG.  1   , according to examples of the disclosure. The processes of method  400  may be performed by the ECM  130 , individually or in conjunction with one or more other components of fuel cell machine  100 . Method  400  allows the fuel cell machine  100  to operate beyond the time when its fuel cell fuel is depleted, in a manner where the fuel cell machine  100  operating time between refueling and/or recharging is increased and/or optimized. 
     At block  402 , the ECM  130  operates the fuel cell machine  100 . In some cases, this operation may be controlled by an operator in the operator station  112  of the fuel cell machine  100 . In other cases, the ECM  130  may be operating the fuel cell machine  100  autonomously, such as based at least in part on one or more commands received from the electronic device  208 . The fuel cell machine  100  may be engaged in any variety of tasks, such as hauling mined ore, harvesting wheat, flattening asphalt, or the like. The ECM  130  may control and/or command the operation of any variety of subsystems, such as the motors  114 , of the fuel cell machine  100  to perform the task in which the fuel cell machine  100  is engaged. The fuel cell machine  100  may be primarily operated using electrical current from the fuel cell  122 . However, at some times, energy from the battery  118  may be used to operate the fuel cell machine  100  at the same time as the fuel cell  122  to power the fuel cell machine  100 , such as when a task or operation of the fuel cell machine  100  requires burst level, or higher than steady-state levels of power, that cannot be supplied by the fuel cell  122  alone. 
     At block  404 , the ECM  130  continues to operate the fuel cell machine  100  as the fuel cell fuel is depleted and until a threshold level of energy remains in the battery  118 . By operating the fuel cell machine  100  beyond the energy available from just the fuel cell fuel, the operating time, range, and/or task completion can be increased relative to operation where the fuel cell machine  100  is only operated until the fuel cell fuel is depleted. The threshold level of energy for determining when the fuel cell machine  100  should stop being used to perform its task may be a level of energy that would be safely sufficient to return the fuel cell machine to the refueling/charging station  202 . In some cases, this threshold may be variable and/or settable by an operator, such as based on the particular features and/or size of the worksite  200  where the fuel cell machine  100  is being used. 
     In some cases, when the ECM  130  controls the fuel cell machine  100  to be operated with energy from the battery  118  only, the fuel cell machine  100  may be operated in a normal mode, where there are no additional limits placed on the operation of the fuel cell machine  100 . In these cases, the power delivery capability of the battery  118  may be sufficient to operate the fuel cell machine  100  without limits. In other cases, when the ECM  130  controls the fuel cell machine  100  to be operated with energy from the battery  118  only, the fuel cell machine  100  may be operated in a derated mode. This derated mode, as described herein, may reduce the peak power consumed by the fuel cell machine  100 , such that the peak power draw by the subcomponents (e.g., motors  114 , controller, etc.) do not exceed the power rating of the battery  118 . As a result, the ECM  130  may prevent damaging and/or excessively depleting the battery  118  during fuel cell machine  100  operation using energy only from the battery  118 . This derated mode may manifest in a reduced/limited speed, a reduced/limited force, or the like of actions performed by the fuel cell machine  100 . In some cases, the ECM  130  may engage in this derated mode by continuously monitoring the power usage of the fuel cell machine  100 , and when power usage approaches the rated limits of the battery  118 , the ECM  130  may control various other controllers (e.g., the motor controller  116 ) to reduce power usage. In other cases, the ECM  130  may implement a limit on speed, force, and/or other parameters of actions performed by the fuel cell machine  100  to stay within the bounds of the battery&#39;s power rating. 
     At block  406 , when only a threshold level of energy is available to operate the fuel cell machine  100 , the ECM  130  moves the fuel cell machine  100  to the refueling/charging station  202 . In autonomous operation, the ECM  130  may move the fuel cell machine  100  to the refueling/charging station  202  without operator intervention. In other cases, the ECM  130  may indicate to an operator that a threshold level of energy is remaining for operating the fuel cell machine  100  and/or indicate to the operator that the fuel cell machine should be returned to the refueling/charging station  202 . In some cases, the ECM  130  may also indicate, during the operation of the fuel cell machine  100 , the amount of total energy available to operate the fuel cell machine  100 , such as from the fuel cell fuel remaining in the fuel tank  126  and the battery  118 . 
     It should be understood that the operations of method  400  allow the fuel cell machine  100  to operate for a longer time and/or have a greater range than would otherwise be possible with conventional ways of operating fuel cell machines  100 . By fully or nearly fully depleting the battery  118  in performing the task before refueling and/or recharging the fuel cell machine  100 , a greater time and or performed work is realized between refueling and/or recharging the fuel cell machine  100 . Additionally, with the fuel cell machine  100  having a relatively high ratio of battery capacity  118  to fuel tank  126  capacity, such as a ratio of about 0.2 to about 1.5, the fuel cell machine  100  can operate for a longer time between refueling and/or recharging relative to conventional fuel cell machines. This results in improved productivity, efficiency, and equipment usage at the worksite  200 . 
     It should be noted that some of the operations of method  400  may be performed out of the order presented, with additional elements, and/or without some elements. Some of the operations of method  400  may further take place substantially concurrently and, therefore, may conclude in an order different from the order of operations shown above. 
       FIG.  5    is a flow diagram depicting an example method  500  for displaying a level of energy available for operating the fuel cell machine  100  of  FIG.  1   , according to examples of the disclosure. The processes of method  500  may be performed by the ECM  130 , individually or in conjunction with one or more other components of fuel cell machine  100 . Method  500  allows the fuel cell machine  100  to provide an indication of a combined amount of energy from the fuel cell fuel and the battery  118  available to operate the fuel cell machine  100 . 
     At block  502 , the ECM  130  may receive an indication of an amount of available fuel cell fuel. As discussed herein, this indication of the amount of fuel cell fuel may be received from the fuel tank controller  128 . The amount of fuel cell fuel may be received in any suitable units, such as pressure, weight, etc. The ECM  130  may convert the amount of fuel cell fuel remaining into an equivalent level of energy available from the remaining fuel cell fuel. 
     At block  504 , the ECM  130  may receive an indication of an amount of charge remaining in the battery  118 . As discussed herein, this indication of the amount of charge may be received from the battery controller  120  as any suitable metric, such as SOC. Regardless of the metric received from the battery controller  120  indicating the level of remaining charge in the battery  118 , the ECM  130  may convert metric to an equivalent level of energy available from the battery  118 . 
     At block  506 , the ECM  130  may determine a combined energy available to operate the fuel cell machine  100  based at least in part on the amount of available fuel cell fuel and the amount of charge remaining in the battery  118 . In some examples, this may entail summing the remaining energy available from the fuel cell fuel and the energy remaining in the battery  118 . Alternatively or in addition, the ECM  130  may determine a remaining estimated time of operation of the fuel cell machine  100 . This determination may be based at least in part on the total available energy from the remaining fuel cell fuel and the battery  118 , as well as an estimate of the energy usage per unit time (e.g., power) of the time being performed. In some cases, the power usage corresponding to the task may be an extrapolation of the power usage during the operation of the task by the fuel cell machine  100 . Thus, the ECM  130  may monitor the power usage while performing the task and use that information to estimate the ongoing power usage, for the purposes of estimating the amount of remaining operation time of the fuel cell machine  100  performing the current task. 
     At block  508 , the ECM  130  may cause the combined energy available to operate the fuel cell machine  100  to be indicated. ECM  130  may provide an updated level of energy remaining to be displayed on the energy gauge  136 . In some cases, the ECM  130  may repeatedly perform method  500  to repeatedly provide an updated combined energy available to operate the fuel cell machine  100  to be indicated on the energy gauge  136 . Alternatively or additionally, the ECM  130  may cause the energy gauge  136  to display the remaining estimated time of operation of the fuel cell machine  100 , the remaining estimated range of the fuel cell machine  100 , or the like. In some cases, the ECM  130  may cause the level of energy remaining to operate the fuel cell machine  100  to be transmitted to the electronic device  208  to be displayed remotely, such as to the operator  214 . 
     It should be understood that the operations of method  500  allow the fuel cell machine  100  to display, such as to a human operator, the amount of total energy available to perform tasks, where this total energy is greater than what would be available had the fuel cell machine been operated according to conventional mechanisms of operation. This display of the total energy available allows the fuel cell machine  100  to operate for relatively longer times between refueling and/or recharging. This results in improved productivity, efficiency, and equipment usage at the worksite  200 . 
     It should be noted that some of the operations of method  500  may be performed out of the order presented, with additional elements, and/or without some elements. Some of the operations of method  500  may further take place substantially concurrently and, therefore, may conclude in an order different from the order of operations shown above. 
       FIG.  6    is a flow diagram depicting an example method  600  for performing a task using the fuel cell machine  100  of  FIG.  1   , according to examples of the disclosure. The processes of method  600  may be performed by the ECM  130 , individually or in conjunction with one or more other components of fuel cell machine  100 . 
     At block  602 , the ECM  130  may determine a task to be performed by the fuel cell machine  100 . In some cases, the ECM  130  may be commanded, such as by the electronic device  208  or other remote controller, to perform the task in an autonomous or semi-autonomous way. In other cases, a human operator, such as a human operator seated in the operator station  112 , may instruct the ECM  130  to perform the task. 
     At block  604 , the ECM  130  may determine an amount of power needed by the fuel cell machine  100  to perform the task. The ECM  130  may determine the energy per unit time (e.g., an average power) to perform the task by any suitable mechanism, such as by using a look-up table that lists the energy per unit time usage for the task. In other cases, the ECM  130  may keep track of energy and/or power requirements when the fuel cell machine  100  previously performed the same or similar tasks and use those values as an estimate of the amount of energy expended per unit time by the fuel cell machine to perform the task. In yet other cases, the ECM  130  may commence the task and make a determination of the amount of energy being expended per unit time to perform the task. 
     At block  606 , the ECM  130  may determine a combined energy available to operate the fuel cell machine  100  based at least in part on the amount of available fuel cell fuel and the amount of charge remaining in the battery  118 . This combined energy may be determined, for example, by the processes of method  500 , as discussed in conjunction with  FIG.  5    herein. The combined available energy may be determined by summing the amount of energy available from the remaining fuel cell fuel in the fuel tank  126  and the energy available from the battery  118 . 
     At block  608 , the ECM may determine an amount of time the task can be performed by the fuel cell machine  100  based at least in part on the amount of power to be expended by the fuel cell machine  100  to perform the task and the combined energy available to operate the fuel cell machine  100 . The ECM  130  may divide the total available energy by the power requirement to arrive at an estimate of the period of time that the fuel cell machine  100  can perform the task. In some cases, the ECM  130  may divide less than the total available energy (e.g., by reserving a safety margin and/or sufficient energy needed to return to the refueling/charging station  202 ) by the power requirement to arrive at an estimate of the period of time that the fuel cell machine  100  can perform the task. In some cases, the ECM  130  may estimate the amount of energy depleted from the battery while the fuel cell machine  100  is still primarily operating using fuel cell fuel to make the determination of the time the task can be performed by the fuel cell machine  100 . 
     At block  610 , the ECM  130  may cause the fuel cell machine  100  to perform the task for the amount of time. This task may be performed autonomously, semi-autonomously, and/or manually. By determining the time for operating the fuel cell machine  100 , the total energy available is not depleted before the fuel cell machine  100  is returned to the refueling/charging station  202 , while the total operating time between refueling and/or recharging of the fuel cell machine  100  can be increased and/or optimized. Initially, the task may be performed using energy from the fuel cell  122  or both the fuel cell  122  and the battery  118 . As the fuel cell fuel is depleted, the task may be performed using energy from the battery  118  only. 
     In some cases, when the ECM  130  controls the fuel cell machine  100  to be operated with energy from the battery  118  only, the fuel cell machine  100  may be operated in a normal mode, where there are no additional limits placed on the operation of the fuel cell machine  100 . In these cases, the power delivery capability of the battery  118  may be sufficient to operate the fuel cell machine  100  without limits. In other cases, when the ECM  130  controls the fuel cell machine  100  to be operated with energy from the battery  118  only, the fuel cell machine  100  may be operated in a derated mode. This derated mode, as described herein, may reduce the peak power consumed by the fuel cell machine  100 , such that the peak power draw by the subcomponents (e.g., motors  114 , controller, etc.) do not exceed the power rating of the battery  118 . As a result, the ECM  130  may prevent damaging and/or excessively depleting the battery  118  during the fuel cell machine  100  operation using energy only from the battery  118 . This derated mode may manifest in a reduced/limited speed, a reduced/limited force, or the like of actions performed by the fuel cell machine  100 . In some cases, the ECM  130  may engage this derated mode by continuously monitoring the power usage of the fuel cell machine  100 , and when power usage approaches the rated limits of the battery  118 , the ECM  130  may control various other controllers (e.g., the motor controller  116 ) to reduce power usage. In other cases, the ECM  130  may implement a limit on speed, force, and/or other parameters of actions performed by the fuel cell machine  100  to stay within the bounds of the battery&#39;s power rating. 
     At block  612 , the ECM  130  may cause the fuel cell machine  100  to move to the refueling/charging station  202 . In autonomous operation, the ECM  130  may move the fuel cell machine  100  to the refueling/charging station  202  without operator intervention. In other cases, the ECM  130  may indicate to an operator that a threshold level of energy is remaining for operating the fuel cell machine  100  and/or indicate to the operator that the fuel cell machine should be returned to the refueling/charging station  202 . In some cases, the ECM  130  may also indicate, during the operation of the fuel cell machine  100 , the amount of total energy available to operate the fuel cell machine  100 , such as from the fuel cell fuel remaining in the fuel tank  126  and the battery  118 . 
     In some cases, the ECM  130  may continuously and/or periodically repeat the method  600  to refine the remaining time to operate the fuel cell machine  100  in performing the task. In some cases, the method  600  may be repeated using refined and/or updated estimates of power expenditure, such as based at least in part on extrapolating the amount of power used while the fuel cell machine  100  was performing the task. By repeating method  600 , better estimates may be made of the operating time remaining of the fuel cell machine  100  as the fuel cell machine  100  performs the task. 
     It should be noted that some of the operations of method  600  may be performed out of the order presented, with additional elements, and/or without some elements. Some of the operations of method  600  may further take place substantially concurrently and, therefore, may conclude in an order different from the order of operations shown above. 
       FIG.  7    is a flow diagram depicting an example method  700  for operating the fuel cell machine  100  of  FIG.  1   , according to examples of the disclosure. The processes of method  700  may be performed by the ECM  130 , individually or in conjunction with one or more other components of fuel cell machine  100 . 
     At block  702 , the ECM  130  may determine a task to be performed by the fuel cell machine  100 . In some cases, the ECM  130  may be commanded, such as by the electronic device  208  or other remote controller, to perform the task in an autonomous or semi-autonomous way. In other cases, a human operator, such as a human operator seated in the operator station  112 , may instruct the ECM  130  to perform the task. 
     At block  704 , the ECM  130  may cause the fuel cell machine  100  to commence and/or continue to perform the task. As discussed herein, the ECM  130  may cause the fuel cell machine  100  to perform the task in an autonomous or semi-autonomous fashion, in some cases. In other cases, the ECM  130  may receive indications of operator interactions with components of the fuel cell machine  100  to perform the task. 
     At block  706 , the ECM  130  may receive an indication of an amount of fuel cell fuel remaining. As discussed herein, this indication of the amount of fuel cell fuel may be received from the fuel tank controller  128 . The amount of fuel cell fuel may be received in any suitable units, such as pressure, weight, etc. The ECM  130  may convert the amount of fuel cell fuel remaining into an equivalent level of energy available from the remaining fuel cell fuel. 
     At block  708 , the ECM  130  may determine if the fuel cell fuel is depleted. This determination may be based at least in part on the indication of the amount of fuel cell fuel remaining, as receive by the ECM  130  at block  706 . If the indication of the amount of fuel cell fuel remaining is substantially zero or within a margin of zero, the ECM  130  may determine that the fuel cell fuel is depleted. Generally, during the operation of the fuel cell machine  100  the fuel cell fuel may be depleted before the battery  118  is depleted. If the ECM  130  determines that the fuel cell fuel is not depleted, the method  700  may return to block  704  to continue performing the task. 
     If at block  712 , the ECM  130  determines that the fuel cell fuel is depleted, then at block  710 , where the ECM  130  may receive an indication of an amount of charge remaining in the battery  118 . As discussed herein, this indication of the amount of charge may be received from the battery controller  120  as any suitable metric, such as SOC. Regardless of the metric received from the battery controller  120  indicating the level of remaining charge in the battery  118 , the ECM  130  may convert metric to an equivalent level of energy available from the battery  118 . 
     At block  712 , the ECM  130  may determine if the battery  118  is within a threshold charge of being depleted. The threshold charge level may be a level of charge needed to safely return the fuel cell machine  100  to the refueling/charging station  202 . If the ECM  130  determines that the battery  118  is not within a threshold charge level of depletion, then the method  700  may proceed to block  714  to continue performing the task. The ECM  130  may periodically receive the indication of the amount of charge remaining in the battery, at block  710 , and periodically make a determination of whether the battery  118  is within a threshold charge of being depleted, so that the fuel cell machine  100  can be refueled and/or recharged before the battery  118  is fully depleted. 
     In some cases, when the ECM  130  controls the fuel cell machine  100  to be operated with energy from the battery  118  only, the fuel cell machine  100  may be operated in a normal mode, where there are no additional limits placed on the operation of the fuel cell machine  100 . In these cases, the power delivery capability of the battery  118  may be sufficient to operate the fuel cell machine without limits. In other cases, when the ECM  130  controls the fuel cell machine  100  to be operated with energy from the battery  118  only, the fuel cell machine  100  may be operated in a derated mode. This derated mode, as described herein, may reduce the peak power consumed by the fuel cell machine  100 , such that the peak power draw by the subcomponents (e.g., motors  114 , controller, etc.) do not exceed the power rating of the battery  118 . As a result, the ECM  130  may prevent damaging and/or excessively depleting the battery  118  during the fuel cell machine  100  operation using energy only from the battery  118 . This derated mode may manifest in a reduced/limited speed, a reduced/limited force, or the like of actions performed by the fuel cell machine  100 . In some cases, the ECM  130  may engage this derated mode by continuously monitoring the power usage of the fuel cell machine  100 , and when power usage approaches the rated limits of the battery  118 , the ECM  130  may control various other controllers (e.g., the motor controller  116 ) to reduce power usage. In other cases, the ECM  130  may implement a limit on speed, force, and/or other parameters of actions performed by the fuel cell machine  100  to stay within the bounds of the battery&#39;s power rating. 
     If at block  712 , the ECM  130  determines that the battery  118  is within a threshold of being depleted, then the method  700  may proceed to block  716 , where the ECM  130  causes the fuel cell machine  100  to be moved to the refueling/charging station  202 . In autonomous operation, the ECM  130  may move the fuel cell machine  100  to the refueling/charging station  202  without operator intervention. In other cases, the ECM  130  may indicate to an operator that a threshold level of energy is remaining for operating the fuel cell machine  100  and/or indicate to the operator that the fuel cell machine should be returned to the refueling/charging station  202 . In some cases, the ECM  130  may also indicate, during the operation of the fuel cell machine  100 , the amount of total energy available to operate the fuel cell machine  100 , such as from the fuel cell fuel remaining in the fuel tank  126  and the battery  118 . 
     It should be noted that some of the operations of method  700  may be performed out of the order presented, with additional elements, and/or without some elements. Some of the operations of method  700  may further take place substantially concurrently and, therefore, may conclude in an order different from the order of operations shown above. 
       FIG.  8    is a block diagram of an example engine control module (ECM) that may operate the fuel cell machine of  FIG.  1   , according to examples of the disclosure. The descriptions of other controllers that may be included in the fuel cell machine  100  may be similar to the descriptions of the ECM  130  herein. The ECM  130  includes one or more processor(s)  802 , one or more input/output (I/O) interface(s)  804 , one or more communication interface(s)  806 , one or more storage interface(s)  808 , and computer-readable media  810 . 
     In some implementations, the processors(s)  802  may include a central processing unit (CPU), a graphics processing unit (GPU), both CPU and GPU, a microprocessor, a digital signal processor or other processing units or components known in the art. Alternatively, or in addition, the functionally described herein can be performed, at least in part, by one or more hardware logic components. For example, and without limitation, illustrative types of hardware logic components that may be used include field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), system-on-a-chip systems (SOCs), complex programmable logic devices (CPLDs), etc. Additionally, each of the processor(s)  802  may possess its own local memory, which also may store program modules, program data, and/or one or more operating systems. The one or more processor(s)  802  may include one or more cores. 
     The one or more input/output (I/O) interface(s)  804  may enable the ECM  130  to detect interaction with an operator of the fuel cell machine  100 . For example, the operator may press an accelerator, pull a lever, press a brake, or perform any other activity to indicate a desired action of the fuel cell machine  100 . These activities on the part of the operator may be provided as operator signals  220  that are received by the ECM  130 . Thus, the I/O interface(s)  804  may include and/or enable the ECM  130  to receive indications of what actions the fuel cell machine  100  is to perform. 
     The network interface(s)  806  may enable the ECM  130  to communicate via the one or more network(s). The network interface(s)  806  may include a combination of hardware, software, and/or firmware and may include software drivers for enabling any variety of protocol-based communications, and any variety of wireline and/or wireless ports/antennas. For example, the network interface(s)  806  may comprise one or more of WiFi, cellular radio, a wireless (e.g., IEEE 802.1x-based) interface, a Bluetooth® interface, and the like. In some cases, if a remote control is used to control the fuel cell machine  100 , one or more operator signals may be received by the ECM  130  from a remote controller of the fuel cell machine  100 . 
     The storage interface(s)  808  may enable the processor(s)  802  to interface and exchange data with the computer-readable medium  810 , as well as any storage device(s) external to the ECM  130 . The storage interface(s)  808  may further enable access to removable media. 
     The computer-readable media  810  may include volatile and/or nonvolatile memory, removable and non-removable media implemented in any method or technology for storage of information, such as computer-readable instructions, data structures, program modules, or other data. Such memory includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile discs (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, RAID storage systems, or any other medium which can be used to store the desired information and which can be accessed by a computing device. The computer-readable media  810  may be implemented as computer-readable storage media (CRSM), which may be any available physical media accessible by the processor(s)  802  to execute instructions stored on the memory  810 . In one basic implementation, CRSM may include random access memory (RAM) and Flash memory. In other implementations, CRSM may include, but is not limited to, read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), or any other tangible medium which can be used to store the desired information, and which can be accessed by the processor(s)  802 . The computer-readable media  810  may have an operating system (OS) and/or a variety of suitable applications stored thereon. The OS, when executed by the processor(s)  802  may enable management of hardware and/or software resources of the ECM  130 . 
     Several components such as instruction, data stores, and so forth may be stored within the computer-readable media  810  and configured to execute on the processor(s)  802 . The computer readable media  810  may have stored thereon an operator signal manager  812 , a task manager  814 , a fuel level manager  816 , a battery manager  818 , an energy gauge manager  820 , and a recharge/refuel manager  822 . It will be appreciated that each of the components  812 ,  814 ,  816 ,  818 ,  820 ,  822  may have instructions stored thereon that when executed by the processor(s)  802  may enable various functions pertaining to operating the fuel cell machine  100 , as described herein. 
     The instructions stored in the operator signal manager  812 , when executed by the processor(s)  802 , may configure the ECM  130  to receive operator signals from one or more actuators of the fuel cell machine  100 . These actuators may provide operator signals  220  that correspond to qualities of how the motors  114  and/or other components of the fuel cell machine  100  are to be run, such as the power output, RPMs, duration, etc. of running the motors  114  and/or direction of steering. 
     The instructions stored in the task manager  814 , when executed by the processor(s)  802 , may configure the ECM  130  to control the fuel cell machine  100  to perform tasks. In some cases, the tasks may be performed in an autonomous and/or semi-autonomous manner. In other cases, the ECM  130  may receive indications of operator interactions, such as from an operator in the operator station  112 , to control the fuel cell machine  100 . 
     The instructions stored in the fuel level manager  816 , when executed by the processor(s)  802 , may configure the ECM  130  to receive status pertaining to the amount of fuel cell fuel remaining in the fuel tank  126 . This indication of the remaining fuel may be received from the fuel tank controller 128  via any suitable communicative link. In some cases, the ECM  130  may solicit the remaining fuel level in the fuel tank  126  from the fuel tank controller  128  to receive an indication of the remaining fuel level. 
     The instructions stored in the battery manager  818 , when executed by the processor(s)  802 , may configure the ECM  130  to receive an indication of the amount of energy and/or charge level remaining in the battery  118 . This information may be received from the battery controller  120 . The ECM  130  may also be configured to provide any suitable type of control function for the battery  118 . The ECM  130  may further control, such as via the battery controller  120 , when the battery  118  is to be used to provide power to operate the fuel cell machine  100 , such as operating various components of the fuel cell machine  100  (e.g., motors  114 ). 
     The instructions stored in the energy gauge manager  820 , when executed by the processor(s)  802 , may configure the ECM  130  to provide an indication of the total level of energy available to operate the fuel cell machine from the remaining fuel cell fuel and the remaining charge in the battery  118 . The ECM  130  may also be configured to transmit this information, such as via wireless signals  206 , to the electronic device  208  or other suitable remote controlling device. 
     The instructions stored in the recharge/refuel manager  822 , when executed by the processor(s)  802 , may configure the ECM  130  to autonomously or semi-autonomously move the fuel cell machine  100  to the refueling/charging station  202 . In other cases, the ECM  130  may provide an indication to an operator that the fuel cell machine  100  is to be moved to the refueling/charging station  202 , such as when the available energy remaining for the fuel cell machine  100  is within a threshold level of being depleted. 
     The disclosure is described above with reference to block and flow diagrams of systems, methods, apparatuses, and/or computer program products according to the disclosure. It will be understood that one or more blocks of the block diagrams and flow diagrams, and combinations of blocks in the block diagrams and flow diagrams, respectively, can be implemented by computer-executable program instructions. Likewise, some blocks of the block diagrams and flow diagrams may not necessarily need to be performed in the order presented or may not necessarily need to be performed at all, according to some examples of the disclosure. 
     Computer-executable program instructions may be loaded onto a general-purpose computer, a special-purpose computer, a processor, or other programmable data processing apparatus to produce a particular machine, such that the instructions that execute on the computer, processor, or other programmable data processing apparatus create means for implementing one or more functions specified in the flowchart block or blocks. These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means that implement one or more functions specified in the flow diagram block or blocks. As an example, the disclosure may provide for a computer program product, comprising a computer usable medium having a computer readable program code or program instructions embodied therein, said computer readable program code adapted to be executed to implement one or more functions specified in the flow diagram block or blocks. The computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational elements or steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions that execute on the computer or other programmable apparatus provide elements or steps for implementing the functions specified in the flow diagram block or blocks. 
     It will be appreciated that each of the memories and data storage devices described herein can store data and information for subsequent retrieval. The memories and databases can be in communication with each other and/or other databases, such as a centralized database, or other types of data storage devices. When needed, data or information stored in a memory or database may be transmitted to a centralized database capable of receiving data, information, or data records from more than one database or other data storage devices. In other cases, the databases shown can be integrated or distributed into any number of databases or other data storage devices. 
     INDUSTRIAL APPLICABILITY 
     The present disclosure describes systems and methods for extending the range of fuel cell machines  100 , such as mining machines (e.g., a mining truck) that operates using fuel cell fuel (e.g., hydrogen) and also has energy stored in a battery  118 . These fuel cell machines  100  provide several advantages, such as reduced carbon, particulate, and/or VOC emissions. Additionally, these fuel cell machines  100  may be advantageous to operate at worksites  200  that are not electrified (e.g., worksites  200  lacking electrical transmission and/or generation infrastructure) and/or where it is difficult to transport other fuels. The systems and methods disclosed herein allow for extending and/or maximizing the range and/or the time of operation of fuel cell machines  100  by operating the fuel cell machine  100  beyond the depletion of fuel cell fuel and nearly to depletion of the charge in the battery  118 . Furthermore, the capacity of battery energy to the capacity of the fuel cell energy may be advantageous to operate the fuel cell machine  100 , as disclosed herein. 
     By the fuel cell machine  100  and the ECM  130  disclosed herein, the viability of fuel cell machines  100  for construction, mining, farming, and other activities is improved, by overcoming limits on their usage time between refueling and/or recharging. The ECM  130  and operation of the fuel cell machine  100  disclosed herein allows for relatively long times and/or ranges between refueling and/or recharging. Thus, fuel cell machines  100  can be deployed at the worksite  200  and operators will be able to operate the fuel cell machines  100  for relatively long periods of time to complete tasks at the worksite  200 . The increased usable range and operating times of fuel cell machines  100 , as disclosed herein, provides for improved efficiency and usage rates of fuel cell machines  100 . This leads to improved levels of worker and capital efficiency, greater uptime and greater field usage of construction equipment, and greater efficiency of construction, mining, agriculture, and/or transportation projects. 
     Although the systems and methods of fuel cell machines  100  are discussed in the context of a mining trucks and other mining machinery, it should be appreciated that the systems and methods discussed herein may be applied to a wide array of machines and vehicles across a wide variety of industries, such as construction, mining, farming, transportation, military, combinations thereof, or the like. For example, the range and/or operating time extension mechanism disclosed herein may be applied to a compactor in the paving industry or a harvester in the farming industry. 
     While aspects of the present disclosure have been particularly shown and described with reference to the examples above, it will be understood by those skilled in the art that various additional examples may be contemplated by the modification of the disclosed machines, systems and methods without departing from the spirit and scope of what is disclosed. Such examples should be understood to fall within the scope of the present disclosure as determined based upon the claims and any equivalents thereof. 
     Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein.