Patent Publication Number: US-2023155631-A1

Title: Smart labels comprising multiple wireless radios and methods of operating thereof

Description:
BACKGROUND 
     Wireless radios can be utilized in various types of devices for transmitting and receiving various types of data. Some examples of such devices include active radio-frequency identification (RFID) tags, smart meters, security sensors, door locks, and wireless cold-chain data loggers. These devices are equipped with batteries for powering these wireless radios and performing other functions. Typically, a device incorporates only one wireless radio. As such, the battery, power management, and functionality are specifically tailored and limited by this one wireless radio. For example, a narrowband internet of things (NB-IoT) radio typically requires power pulses of 1-2 W (e.g., at a voltage of 5V) for its operation. A long-range (LoRa) radio requires pulses of 100-250 mW (e.g., at a voltage of 2.5V), while a Bluetooth low energy (BLE) radio requires pulses of 3-15 mW (e.g., a voltage of 1.5V). When the battery is discharged below the level, at which it can power the radio, the radio can no longer operate. However, the remaining battery capacity is typically quite substantial (e.g., more than 50% of the initial capacity or even more than 75% of the initial capacity) for many types of batteries. Yet this remaining capacity is available only at lower power levels, below the operating requirements of the radio. 
     What is needed are new methods and systems for power management of smart labels and tags with multiple wireless radios. 
     SUMMARY 
     Described herein are smart labels, each comprising multiple wireless radios, and methods of operating such labels. For example, a smart label comprises a battery and two wireless radios having different power requirements. When the battery is no longer able to support a high-power radio (e.g., NB-IoT), the battery can still power a low-power (e.g., BLE). A battery can be specially configured and/or controlled to support the multi-radio operation of the smart label. For example, a battery can include multiple battery cells with configurable connections among these cells and radios. Furthermore, some battery components can be shared by wireless radios. The battery can also power other components of the smart label, such as sensors (e.g., temperature, acceleration, pressure, package integrity, global positioning), memory, and input/output components. In some examples, multiple smart labels form a mesh network, designed to lower the total power consumption by the radios of these labels. 
     These and other embodiments are described further below with reference to the figures. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIGS.  1 A and  1 B  are examples of voltage profiles corresponding to different operating conditions of battery cells. 
         FIGS.  1 C,  1 D, and  1 E  illustrate the performance of printed batteries comprising four zinc-manganese dioxide cells at 23° C., 60° C., and −20° C. 
         FIG.  2    is a schematic illustration of a smart label comprising a battery, a first wireless radio, a second wireless radio, and other components, in accordance with some examples. 
         FIGS.  3 A- 3 E  are schematic illustrations of a smart label, showing various arrangements and connections of multiple battery cells for powering two wireless radios, in accordance with some examples. 
         FIGS.  4 A and  4 B  are schematic cross-sectional side views of a multi-modal battery cell, in accordance with some examples. 
         FIG.  5 A  is a schematic cross-sectional side view of a smart label illustrating specific integrations of a battery and two antennas, in accordance with some examples. 
         FIGS.  5 B and  5 C  are schematic cross-sectional top and side views of a single-layer-electrode cell, in which the current collectors are used as antennas of wireless radios, in accordance with some examples. 
         FIG.  6    is a schematic illustration of a mesh network formed by multiple smart labels, which may be positioned on a common package, in accordance with some examples. 
         FIG.  7    is a process flowchart corresponding to a method of operating a smart label, in accordance with some examples. 
     
    
    
     DETAILED DESCRIPTION 
     In the following description, numerous specific details are outlined in order to provide a thorough understanding of the presented concepts. The presented concepts may be practiced without some or all of these specific details. In other instances, well-known process operations have not been described in detail to not unnecessarily obscure the described concepts. While some concepts will be described in conjunction with the specific embodiments, it will be understood that these embodiments are not intended to be limiting. 
     Introduction 
     Wireless radios can be characterized based on their communication protocols, such as near-field communication (NFC), ultra-wideband (UWB), Bluetooth low energy (BLE), long-range (LoRa) radio, narrowband internet of things (NB-IoT), and even satellite. These communication protocols have been developed for different communication needs and require different power levels. For example, a BLE radio is used for meter-range data transmission and requires pulses of 3-15 mW. A LoRa protocol is used for kilometer-range data transmission and requires pulses of 100-250 mW. An NB-IoT protocol- for multi-kilometer-range data transmission and requires pulses of 1-2 W. These power pulses also correspond to different voltage requirements, which are typically higher for higher-power radios. 
     Described herein are smart labels, each comprising multiple wireless radios, and methods of operating thereof. Specifically, these multiple wireless radios operate using different protocols (e.g., an NB-IoT and a BLE) and have different power requirements (e.g., 1-2 W and 3-15 mW). Each smart label also comprises a battery, formed using one or more battery cells, for powering the radios. In some examples, each battery cell is managed by a controller, configured to select the cell for specific power demands as further described below. The battery is specifically configured and/or controlled to ensure the operation of one or both radios over a long period. For example, when a battery is discharged below a level needed for the operation of a higher-power radio, the battery can be still used to operate a lower-power radio. Furthermore, a lower-power radio may be used whenever possible (instead of a high-power radio) to preserve the overall battery charge. In some examples, the battery also powers other components of the smart label, such as sensors, memory, power controller, and input/output components. Furthermore, the battery may comprise multiple battery cells. The connections among these battery cells may be specifically configured and/or controlled to provide the power output needed by each wireless radio. Using multiple wireless radios expands the functionality, range, and power management of smart labels, in comparison to, e.g., single-radio labels. Finally, smart labels can be configured to recharge batteries, e.g., wirelessly, while proximate to a charger. 
     This multi-radio functionality can be demonstrated using a specific example, e.g., a smart label comprising an NB-IoT radio and a BLE radio. In this example, the NB-IoT radio may be used for long-range data transmission, while the BLE radio may be used for short-range data transmission. Since the BLE radio uses less power, the overall battery capacity is preserved when the BLE radio can be used instead of the NB-IoT radio. Furthermore, the NB-IoT communication may not be available due to various external factors (e.g., no external NB-IoT radios are available for communication with the smart label) and/or internal factors (e.g., the battery is discharged below the level at which the NB-IoT radio can be powered). However, even when the battery is discharged below that level, the battery can still power the BLE radio. As such, any data available at the smart level can be still transmitted. Furthermore, multiple smart labels can form a mesh network, in which these smart labels communicate with each other using the lower-power radio (e.g., the BLE radio in the above example). The smart labels can designate one label for external communication using, for example, a higher-power radio (e.g., the NB-IoT radio in the above example). This mesh network approach preserves the total power of all smart labels. In some examples, the external communication designation is switched from one smart label to another (e.g., based on the battery operating parameters). 
     A smart label may include various features and components for powering multiple wireless radios or, more specifically, for ensuring different levels of power supplied to different wireless radios. In some examples, the smart label comprises a step-down power converter, which allows bringing the voltage (and the power) of the battery to the level needed for each wireless radio. In some examples, a power controller is used to form different types of connections within the smart label (e.g., among multiple battery cells forming one battery and two or more wireless radios). For example, multiple battery cells may be interconnected in-series to power an NB-IoT radio, while only one of these battery cells may be used to power a BLE radio. In other examples, different types of battery cells are used for connecting different wireless radios, e.g., a larger cell is used for an NB-IoT radio, while a smaller cell is used for a BLE radio. 
     The battery performance is determined in part by the battery chemistry, design (e.g., size, shape), environmental factors (e.g., temperature), and the like. However, most battery cells have the same general voltage response to the power drawn at different states of charge as, e.g., is shown in  FIG.  1 A . Specifically,  FIG.  1 A  illustrates a voltage profile as a function of the discharged capacity for four different discharge rates. The discharge rate of 278 mA is representative of the power drawn by an NB-IoT radio, the discharge rate of 100 mA is representative of the power drawn by a LoRa radio, a discharge rate of 10 mA is representative of the power drawn by a BLE radio, and discharge rate of 1 mA is representative of the power drawn by an NFC radio. Specifically, the discharge curves in  FIG.  1 A  were obtained from batteries comprising four zinc-manganese dioxide cells. These batteries were discharged at the ambient temperature of 23° C. The cells were printed on a patterned substrate, with the total battery thickness being less than 1 millimeter. The footprint of each cell was less than 122 millimeters by 130 millimeters. It should be noted that this form factor is particularly suitable for smart label applications. Overall,  FIG.  1 A  illustrates a lot more capacity is available at lower discharge rates. As such, when the voltage profile drops below a threshold for a high-power radio, the battery can be still used for operating a low-power radio. It should be noted that smart labels may include other (non-radio components, e.g. sensors), which have very low power consumption (e.g., a microamp level current). 
     Without being restricted to any specific theory, it is believed that various electrochemical factors can impact the discharge capabilities of a battery. For example, a high discharge rate can cause the passivation of active material particles, especially in zinc batteries. More specifically, zinc particles can dissolve at high discharge rates causing a release of various byproducts. These byproducts can passivate the remaining zinc particles. In some examples, a battery can take hours, days, and even weeks before another high-rate discharge pulse can be applied, which may be referred to as a relaxation period. In some examples, higher discharge rates cause diffusion limitations in the negative and positive electrodes. As such, some portions of the electrode active materials can remain unused or underutilized. 
     In some examples, wireless radios are configured to perform periodic/cyclic operations. For example, every few minutes or hours, a radio attempts to form a communication channel, effectively searching for nearby signals from other radio gateways, phones, or base stations available for communication over the forward and reverse channels. This part of the overall communication process may be referred to as a handshake. If the communication channel is formed, the radio then can complete data transmission.  FIG.  1 B  illustrates power requirements for an NB-IoT radio during such handshake and transmission stages. 
     As noted above, various environmental factors, such as temperature, can impact the power output and available discharge capacity of a battery.  FIGS.  1 C,  1 D, and  1 E  illustrate the performance of printed batteries comprising four zinc-manganese dioxide cells at 23° C., 60° C., and −20° C., which cover a typical operating range of smart labels. In this example, the discharge profile, shown in  FIG.  1 B , was applied to each cell every 5 minutes. These results illustrate that the battery was able to support 700 NB-IoT transmissions at 23° C., 800 transmissions at 60° C., and 150 transmissions at −20° C. 
     Smart Label Examples 
       FIG.  2    is a schematic illustration of smart label  100 , in accordance with some examples. Smart label  100  comprises battery  130 , first wireless radio  110 , and second wireless radio  120 . Both first wireless radio  110  and second wireless radio  120  are powered by battery  130 . In some examples, various other components of smart label  100  shown in  FIG.  2    and described below are also powered by battery  130 . Second wireless radio  120  has a higher power requirement than first wireless radio  110 . For example, second wireless radio  120  is an NB-IoT radio, while first wireless radio  110  is one of an NFC radio, a BLE radio, or a LoRa radio. In general, each of first wireless radio  110  and second wireless radio  120  can be either an NFC radio, a BLE radio, a LoRa radio, and an NB-IoT radio. One having ordinary skill in the art would recognize that the power requirement of the NB-IoT radio is the highest in this list, followed by the LoRa radio, which is followed by the BLE radio and, finally, by the NFC radio. In some examples, smart label  100  includes additional wireless radios, which may be different from first wireless radio  110  and second wireless radio  120 . 
     Battery  130  is configured to selectively power first wireless radio  110  or second wireless radio  120  based on at least one or more operating parameters of battery  130 . Some examples of these battery operating parameters include, but are not limited to, OCV, temperature, Coulomb counter output, SOH, and sensor readings (e.g., accelerometer, pressure sensor). For example, sensor readings can be used to detect if smart label  100  is in transit or, more specifically, in a particular kind of transit (e.g., air transit, train transit, vehicle transit, last-mile delivery). These factors indicate the power output capabilities of battery  130 . For example, a higher OCV generally corresponds to a higher power output capability (e.g., due to a higher SOC). A higher temperature may also correspond to a higher power output capability. However, the operation of battery  130  may need to be limited upon reaching a certain upper-temperature threshold (e.g., to prevent overheating of battery  130 ). A Coulomb counter indicates the current SOC, and a higher SOC generally corresponds to a higher power output capability. A SOH may be represented by a voltage drop during the last power-drawn pulse, while a higher voltage drop corresponding to a lower power output capability. It should be noted that in addition to the battery operating parameters, various other parameters may be used to selectively power first wireless radio  110  or second wireless radio  120 , such as data availability, communication schedule, communication channel availability, and the like. 
     First wireless radio  110  or second wireless radio  120  may be power directly by battery  130  or, in some examples, by power controller  140 .  FIG.  3 A  illustrates one example of using power controller  140 . In this example, battery  130  comprises four battery cells  139 , interconnected in series. For example, each battery cell may have an operating voltage of 1.5V. As such, the total operating voltage of battery  130  is 6.0V. Power controller  140  is connected to battery  130  and is configured to apply the full battery voltage (e.g., when powering second wireless radio  120 ) or to step down this battery voltage to a lower voltage (e.g., when powering first wireless radio  110 ). For example, first wireless radio  110  is a BLE radio with an operating voltage range of 1-2V. A voltage step-down function is needed to power first wireless radio  110  in this example. In the same or other examples, second wireless radio  120  is a NB-IoT radio with an operating voltage range of 3-6V. The NB-IoT radio can be powered without any or with a much lower voltage stepdown. It should be noted that the operating cell voltage may reduce (e.g., below the 1.5V level) as battery cells  139  reach lower SOC levels, requiring less voltage step-down functionality. The  FIG.  3 A  example allows discharging all battery cells  139  in a uniform manner (e.g., regardless of the energy consumed by either radio). For example, battery cells  139  may have the same state of charge regardless of the number of times either radio was used for data transmission. Furthermore, power controller  140  requires only minimal switching functionality and a step-down voltage function (e.g., connecting a resistor). These simple power control functions allow reducing the size (e.g., thickness and footprint) of smart label  100  and more efficiently use the capacity of battery  130  (e.g., voltage step-down functionality is more efficient than voltage step-up functionality). 
       FIG.  3 B  illustrates another example of smart label  100  that does not use any power controllers. In this example, four battery cells  139  are also interconnected in series. This in-series assembly is then directly connected to second wireless radio  120 . In other words, second wireless radio  120  experiences a combined voltage of four battery cells  139 . However, first battery cell  131  is only connected to first wireless radio  110  and experiences only the voltages of first battery cell  131 . Therefore, first wireless radio  110  is only powered by first battery cell  131 , while second wireless radio  120  is powered by all four battery cells  139 . While first battery cell  131  is used to power both first wireless radio  110  and second wireless radio  120 , it should be noted that the power consumption of first wireless radio  110  can be a lot smaller than that of second wireless radio  120 . For example, a BLE radio requires only 3-15 mW for its operation, while an NB-IoT radio requires 1-2 W (or 200-300 times more). As such, the impact of the BLE radio on the discharge of first battery cell  131  will be minimal in comparison to the NB-IoT radio. Furthermore, eliminating a power controller reduces the cost and size of smart label  100  while improving the battery capacity utilization. 
       FIGS.  3 C and  3 D  illustrate an example of using power controller  140  to manage connections between battery  130  and each of first wireless radio  110  and second wireless radio  120 . Power controller  140  comprises five switches that determine which wireless radio is powered and which battery cells are used to power this radio. While  FIGS.  3 C and  3 D  illustrate battery  130  comprising two battery cells, one having ordinary skills in the art would recognize that any number of battery cells can be controlled in this manner. The number of wireless radios, the number of battery cells, and connection options collectively determine the number and position of switched in power controller  140 . 
       FIG.  3 C  illustrates a state of power controller  140  where first wireless radio  110  is connected to first battery cell  131  and second battery cell  132 , with these two cells being connected in parallel with each other. Second wireless radio  120  is disconnected from first battery cell  131  and second battery cell  132 . In this state, first switch  141  and fourth switch  144  are disconnected/open, while second switch  142 , third switch  143 , and fifth switch  145  are connected/closed. If needed, second battery cell  132  can be disconnected by opening switch  142  and/or fifth switch  145 . In some examples, power controller  140  can have additional switches (not shown) for disconnecting first battery cell  131  while powering first wireless radio  110  with second battery cell  132  or vice versa (disconnecting second battery cell  132  while powering first battery cell  131 ). 
       FIG.  3 D  illustrates a state of power controller  140  where second wireless radio  120  is connected to first battery cell  131  and second battery cell  132 , with these two cells being connected in series thereby combining the voltage of these cells to power second wireless radio  120 . First wireless radio  110  is disconnected from first battery cell  131  and second battery cell  132 . In this state, first switch  141  and fourth switch  144  are connected/closed, while second switch  142 , third switch  143 , and fifth switch  145  are disconnected/open. 
       FIG.  3 E  illustrates another example in which smart label  100  does not use a power controller. In this example, battery  130  comprises two battery cells that have different sizes. Specifically, first battery cell  131  is smaller than second battery cell  132  and is used to power first wireless radio  110 . Second battery cell  132  is larger and is used to power second wireless radio  120 . Because of the larger size, second battery cell  132  can support larger discharge currents than first battery cell  131  and provide higher power. The voltage of first battery cell  131  and second battery cell  132  may be the same or different. For example, second battery cell  132  may have multiple sets of electrodes interconnected in series to provide a higher voltage. 
     Overall, in some examples, smart label  100  comprises power controller  140 . When present, power controller  140  is configured to selectively power first wireless radio  110  or second wireless radio  120  based on the operating parameters received at least in part from battery  130 . Additional examples include communication channel availability for each of first wireless radio  110  and second wireless radio  120 . For example, first wireless radio  110  and second wireless radio  120  may periodically check for the availability of their respective communication channels, which is described as a “handshake” with reference to  FIG.  1 B  above. If only one channel is available, then the data transfer is performed using this channel. In some examples, when both channels are available, power controller  140  may select one or both channels for the data transfer. For example, this selection may depend on the remaining battery capacity (e.g., using a lower-power wireless radio when the battery capacity is below a set threshold), a data type that needs to be transferred, and other factors. 
     Referring to  FIG.  2   , in some examples, smart label  100  comprises one or more sensors  182 . These sensors  182  can be powered by battery  130 . Some examples of sensors  182  include, but are not limited to, thermocouple, a humidity sensor, a pressure sensor, an altimeter, an accelerometer, a drop sensor, a package-integrity sensor, a label identifier, a global positioning sensor GPS, an interrupt sensor (e.g., for detecting the integrity of the package), a conductivity sensor (e.g., to measure the wetness), a proximity sensor, a radiation sensor, a position sensor, a photoelectric sensor, a particle sensor, a motion sensor, a level sensor, a leak sensor, a moisture sensor, a humidity sensor, a gas sensor, a chemical sensor, a force sensor, a fire sensor, an electrical sensor, and a contact sensor. In the same or other examples, smart label  100  also comprises memory  180  configured to store data from sensor  182 . For example, memory  180  aggregates various data from sensors  182  and then transmits this data to first wireless radio  110  and/or second wireless radio  120  for external data transfer. Memory  180  can be powered by battery  130 . In some examples, sensor  182  can measure resistance to determine the temperature. 
     In some examples, smart label  100  comprises input component  184 , such as a microphone, a switch, and the like. Input component  184  can be powered by battery  130 . Input component  184  receives external input (e.g., from a user), which can include various commands (e.g., to respond, to supply available data, to start collecting data, to add new data, to initiate communication, and the like). For example, input component  184  can receive and interpret a voice command, such as “Are you Ok?”, “Was the temperature in spec?”, “When were you shipped?”. 
     In some examples, smart label  100  comprises output component  186 , such as a speaker, a light, and a display. Output component  186  can be powered by battery  130 . Output component  186  can provide output that can be directly interpreted by a user. Some output examples include, but are limited to, turning on a light, displaying a message (e.g., text, warning, and the like), and producing voice output. In some examples, the display displays a quick Response code (QR code). The QR code can convey information about the shipping history, information of the sensors output over a period of time, information about the content of the package, sender or receiver information, or a encode a link to this information. The display may also show the state-of-charge or state-of-health of battery  130 . 
     Referring to  FIG.  2   , in some examples, various components, e.g., first wireless radio  110 , and second wireless radio  120 , can be integrated into the same semiconductor chip  102 . Other components that can be integrated into this semiconductor chip  102  are power controller  140 , memory  180 , and/or sensors  182 . Other integration aspects (e.g., current collectors of battery  130  used as antennas of first wireless radio  110 , and second wireless radio  120 ) are described above. 
     In some examples, smart label  100  is formed in a traditional rectangular shape and size, e.g., 4″×6″, 4″×4″, or 6″×6″ size. Smart label  100  can also be circular in shape, which is beneficial for some applications (e.g., putting on the top of drums). In some examples, smart label  100  can be flexible or conformal to be applied to the side of the drums or bottles. 
     Battery Examples 
     Various types of battery  130  can be used in smart labels  100 . Some examples include, but are not limited to zinc batteries, sodium batteries, or lithium and lithium-ion batteries. In some examples, battery  130  has a total thickness of less than 3 millimeters or, more specifically, less than 2 millimeters. With such small thickness, battery  130  or, more generally, smart label  100  do not protrude too far from shipment containers (to which this smart label  100  is attached) and is less likely to be damaged or torn off during the shipping process. In some examples, battery  130  is flexible, and can be bending around a 3″ core (e.g., a 3″ core is typically used for containing rolls of labels). Battery  130  can be disposable and not classified as dangerous goods (e.g., zinc batteries). For comparison, lithium or lithium-ion batteries of certain size are classified as dangerous goods and can have various shipping restrictions. The operating temperature range of battery  130  can range from −40° C. to +60° C. or, more specifically, from −20° C. to +60° C. (e.g., to be able to transmit the signal in a variety of environmental conditions). 
     In some examples, battery  130  comprises multi-modal battery cell  402  as, e.g., is schematically shown in  FIGS.  4 A and  4 B . Multi-modal battery cell  402  comprises first electrode  410  and second electrode  420 . First electrode  610  and second electrode  420  may have a varying thickness and/or a varying composition. For example,  FIG.  4 A  illustrates an example where each electrode has a thinner portion (e.g., having a larger area) and a thicker portion (e.g., having a smaller area). These thicker portions provide large energy storage, occupying only a small portion of the total area. However, due to the small area, the power rating may be also small (suitable to power first wireless radio  110  but not second wireless radio  120 ). On the other hand, the thinner portion can provide a larger power (suitable to power first wireless radio  110  or second wireless radio  120 ). In some examples, the electrode thickness variation is abrupt (e.g., as shown in  FIG.  4 A ) or gradual (e.g., as shown in  FIG.  4 B ). Different electrode thicknesses of multi-modal battery cell  402  can be used to achieve uniform thickness across the entire footprint of smart label  100 . For example, a thinner portion of multi-modal battery cell  402  can be stacked with other components of smart label  100  (e.g., circuitry) collectively yielding the same thickness as the thicker portion of multi-modal battery cell  402 . From an electrical perspective, the thicker part of multi-modal battery cell  402  is beneficial because this part stores more energy per volume and allows for longer battery life in low drain mode (e.g., a sleep mode, low power transmissions). The thin part of multi-modal battery cell  402  has higher power capability and can be used for supporting high power transmissions. 
     Multi-modal battery cell  402  with variable electrode thickness may be used to maintain the overall label thickness below a set threshold, while effectively filling the volume available for smart label  100 . For example, thinner electrode portions may overlap with other components of smart label  100 , such as sensors, memory, wireless radios, and the like. Furthermore, multi-modal battery cell  402  provides more efficient space utilization in comparison to, e.g., multiple batteries that require interconnections, separation, and other features which occupy space and add to cost. 
     In some examples, a thin “high power” positive and/or negative electrode formulation may include more of the conductive carbons to have lower resistance and lower voltage drop during high power pulse. For example, the thicker electrode may have between 1% to 2% by weight of conductive carbons whereas the thinner electrode may have between 2% to 5% by weight of conductive carbons. More generally, the weight ratio of conductive carbons in the thinner electrode can be between 1.5 and 5 times greater than in the thicker electrode. The electrode with less conductive carbons has a higher energy density (due to a higher weight ratio of active materials) and, therefore, a higher capacity per volume. The difference in the capacity per area of the thinner electrode and thicker electrode can be 1.5 and 3 times. For example, the capacity per area of the thin electrode can be less than 4 mAh/cm 2 , while the capacity per area of the thicker electrode can be greater than 6 mAh/cm 2 . 
     In some examples, battery  130  is a printed battery. Using printing techniques to form various battery components, such as positive active materials layers, electrolyte layers, and negative active material layers provide unique opportunities for battery design and for achieving specific performance characteristics of these batteries. For example, printing an active material layer on a current collector establishes a robust electro-mechanical connection between this active material layer and the current collector. Printing involves depositing a layer of ink onto a base, which may be a substrate or another printed layer. Similarly, printing an electrolyte layer over an active material layer establishes a robust ionic connection between these layers by reducing voids and gaps between these layers. Finally, printing allows making batteries with various shapes (not possible with the conventional wound or stacked batteries). This shape flexibility opens doors to various integration opportunities. 
     In some examples, printing allows fabricating batteries with specific features (not possible with other fabricating techniques), such as electrodes having different thicknesses within a given footprint. Variable-thickness electrodes are difficult to make with conventional blade-over-roll or slot-die coating methods, which are commonly used in battery manufacturing. On the other hand, printing methods described herein can form variable-thickness electrodes in the following ways. For example, first-stage screen printing can be used to form a thin electrode having a first footprint. This electrode is dried before proceeding to the next stage. In a second-stage screen printing, another layer can be formed over the previously-printed electrode. The second-stage screen printing can be performed using the same screen mesh and thickness. The second-stage screen printing can be performed using the same ink or a different ink (e.g., ink with a lower composition of conductive carbons). In some examples, a thin portion of the overall electrode can be printed first, while a thicker portion can be printed next (or side-by-side) using screens of different mesh and thickness. In some examples, these thin-thick printing can be performed in two steps with stencils or with one custom stencil that has a different thickness within a printing footprint. 
     Antenna Integration Examples 
       FIG.  5 A  is a schematic illustration of smart label  100  comprising battery  130  and two wireless radios. The wireless radios share chip  540  (power by battery  130 ) but have different antennas, e.g., first antenna  510  and second antenna  520 . Battery  130  is positioned between first antenna  510  and second antenna  520  thereby preventing signal interference between these antennas. In some examples, first antenna  510 , second antenna  520 , and a current collector of one battery electrodes are formed in the same operation, e.g., by patterning the same metal foil sheet. 
     In some examples, the current collectors of one or both battery electrodes are operable as antennas of one or both wireless radios. More specifically, the electrodes may be stacked such that the distance between the two current collectors is defined by the combined thickness of the negative active material layer, electrolyte layer, and positive active material layer. 
     Alternatively, battery  130  comprises single-layered-electrode battery cell  550  as, e.g., is schematically shown in  FIGS.  5 B and  5 C . Single-layered-electrode battery cell  550  comprises first electrode  551  and second electrode  552 , positioned in one plane (e.g., parallel to the X-Y plane).  FIG.  5 B  illustrates first electrode  551  and second electrode  552  as interdigitated structures, which helps to reduce the ion distance between any pair of adjacent electrodes. One having ordinary skill in the art would appreciate that this distance is inverse proportional to the power rate capabilities of the battery cell. At least one of first electrode  551  or second electrode  552  is operable as an antenna of first wireless radio  110  or second wireless radio  120 . In general, first electrode  551  and second electrode  552  can take any shape while maintaining proximity to each other. The ionic transport between the active material layers is provided by electrolyte layer  553  disposed over first electrode  551  or second electrode  552  as, e.g., is schematically shown in  FIG.  5 C . 
     Smart Label Mesh Network Examples 
     When multiple smart labels  100  are positioned at the same location (e.g., as a part of the same package, such as a pallet), these smart labels  100  may form an internal communication network, which may be referred to as a mesh network. Because of the proximity of smart labels  100 , this internal communication can be performed using a lower-power wireless radio at each smart label  100  thereby reducing the power consumption at each smart label  100 .  FIG.  6    is a schematic illustration of mesh network  600  formed by multiple smart labels  100 , in accordance with some examples. The dotted line illustrated the communication among these smart labels  100  within this mesh network  600 . 
     In some examples, smart labels  100  may designate one or more labels (which may be referred to as dynamic communicators), e.g., smart label  100   a  in  FIG.  6   , for external communication on behalf of all smart labels. In some examples, any label among smart labels in mesh network  600  can be designated as a dynamic communicator. A dynamic communicator can transmit data in both directions or simply broadcast data available at this label. Returning to the example in  FIG.  6    where smart label  100   a  is designated as a dynamic communicator, smart label  100   a  can use its high-power radio to reach external node  620 , which may be not as close to smart label  100   a . Smart label  100   a  may aggregate the data from all labels in mesh network  600  and transmit this data (on behalf of all labels) to external node  620 . In some examples, smart label  100   a  can delegate the responsibility for the external communication and/or the data aggregation to another label, e.g., if the battery of smart label  100   a  drops below a certain state of charge. 
     In some examples, mesh network  600  may monitor whether all smart labels  100  remain present in mesh network  600 . For example, mesh network  600  may report once one label (e.g., smart label  100   x  in  FIG.  6   ) is no longer a part of mesh network  600 . For example, the package carrying this label may be separated from the rest of the packages. In some examples, smart label  100   x  can establish a direct communication channel with external node  620  to report being separated from mesh network  600 . One example of external node  620  is a phone, which can be a gateway. 
     Examples of Smart Label Operations 
       FIG.  7    is a process flowchart corresponding to method  700  of operating smart label  100 , in accordance with some examples. Various examples of smart label  100  are described above. Smart label  100  can be applied to a package and, in some examples, activated, e.g., by allowing battery  130  to power other components of smart label  100 . In some examples, this activation is performed by a user (e.g., after applying smart label  100  to a package). 
     In some examples, method  700  comprises collecting (block  710 ) various data at smart label  100 . Some examples of collected data include, but are not limited to, the temperature history of smart label  100 , humidity history of smart label  100 , acceleration history of smart label  100 , pressure history of smart label  100 , light history of smart label  100 , package integrity history of smart label  100 , position history of smart label  100 . Various types of sensors and/or input devices may be used for this operation. It should be noted that this data collection is an optional operation. In some examples, smart label  100  has a dataset (e.g., previously recorded data, but not directly collected by smart label  100 ) available for transmission. Smart label  100  may have information on the type of product contained in the package, material safety data, serial numbers of the products, information required by the customs (e.g., Harmonized Tariff Codes, country of origin information, or the destination information). This information can be broadcasted via wireless protocol on a periodic basis, or while passing by gateways, or under particular circumstances, such as crossing an international border, or taking off a plane. 
     In some examples, method  700  comprises obtaining (block  720 ) battery parameters, such as the battery OCV, temperature, Coulomb counter output, SOH, and the number of expected transmissions left. These parameters may be later used to determine the capability of battery  130  to power one or both first wireless radio  110  or second wireless radio  120 . For example, if the battery OCV drops below a certain threshold, battery  130  may not be able to power second wireless radio  120  but is still able to power first wireless radio  110 . As an example, battery  130  with an OCV below 2.5-3.0V may not be able to power tNBIoT transmissions but can power LoRa transmissions or BTLE transmissions. Battery  130  with OCV below 2.0V may not be able to power LoRa transmission but can power BTLE transmissions. 
     In some examples, method  700  comprises searching (block  720 ) for communication networks available for first wireless radio  110  and/or second wireless radio  120 . For example, each wireless radio may periodically send a communication request and wait for a response before going back to sleep. This operation is described as a “handshake” with reference to  FIG.  1 B . 
     Method  700  comprises selecting (block  740 ) a wireless radio from first wireless radio  110  or second wireless radio  120  for communication, wherein first wireless radio  110  or second wireless radio  120 . This selection is performed based on, e.g., battery operating parameters listed above (the battery OCV, temperature, Coulomb counter output, SOH, and internal resistance). 
     In some examples, method  700  comprises configuring (block  750 ) the connection between battery  130  and one or both of first wireless radio  110  or second wireless radio  120 . Method  700  comprises transmitting (block  760 ) various data using one or both of first wireless radio  110  or second wireless radio  120 . 
     CONCLUSION 
     Although the foregoing concepts have been described in some detail for purposes of clarity of understanding, it will be apparent that certain changes and modifications may be practiced within the scope of the appended claims. It should be noted that there are many alternative ways of implementing the processes, systems, and apparatuses. Accordingly, the present embodiments are to be considered illustrative and not restrictive.