Patent Publication Number: US-2013252074-A1

Title: Battery module

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a battery module, and more particularly, to a battery module capable of simplifying its internal structure. 
     2. Description of the Related Art 
     A lithium battery has a property of high energy density, and its applications have been expanded from low power electronic products to various high power electrical apparatuses, such as machine tools, E-Bike, E-Scott, and even large vehicles. The different electrical apparatuses require different electrical properties and there are huge differences in the shapes of different product applications; however, the smallest unit for all battery modules is a battery cell. 
     The sizes and electrical properties of the battery modules are different for different electrical apparatuses. According to prior arts, each individual battery module needs a dedicated battery casing and a plurality of battery cells are disposed outside the battery casing and connected in series via a plurality of metallic conductive sheets or wires. 
     Besides, the battery module further includes a control board. The battery cells coupled to the control board perform both charging and discharging operations via the control board. A plurality of wires need to be installed in order for the battery cells to connect with the control board. During a manufacturing process, the wires need to be connected or soldered between the control board and the battery cells, therefore increasing the process complexity and manufacturing working hours. 
     SUMMARY OF THE INVENTION 
     An object of one embodiment of the invention is to provide a battery module. An object of one embodiment of the invention is to provide a battery module for simplifying its wiring structure. 
     According to one embodiment of the invention, a battery module is provided. The battery module includes a plurality of battery devices, a circuit board, a control board and a bus wire. Each battery device includes a plurality of battery cells and at least one conductive sheet for connecting the battery cells. The circuit board includes a circuit layout to which the conductive sheets of the battery devices are electrically connected. The control board is used to control the battery cells of the battery devices. The bus wire is electrically connected between the circuit layout of the circuit board and the control board to cause the control board to electrically connect with the battery devices via the circuit layout of the circuit board and the bus wire. 
     In one embodiment, the at least one conductive sheet of each of the battery devices extends toward the circuit board to electrically connect to the circuit layout of the circuit board. 
     In one embodiment, the circuit board further includes a printed circuit board and a first connector. The circuit layout is disposed on the printed circuit board. The first connector is disposed on the printed circuit board and electrically connected to the circuit layout. The control board further includes a second connector. The bus wire includes a third connector, a fourth connector and a connection wire. The connection wire is electrically connected between the third connector and the fourth connector. The structure of the third connector fits the structure of the first connector to assemble the third connector and the first connector. The structure of the fourth connector fits the structure of the second connector to assemble the fourth connector and the second connector. 
     In one embodiment, the battery module further includes at least one thermal sensor electrically connected to the circuit layout of the circuit board to electrically connect with the control board via the circuit layout of the circuit board and the bus wire. 
     In one embodiment, the circuit layout includes a plurality of conductive wiring lines and a plurality of conductive pads. The conductive wiring lines are electrically connected between the conductive pads and the first connector. The conductive pads are exposed on a surface of the printed circuit board. Each of the battery devices further includes a shell. The battery cells and the at least one conductive are disposed inside the shell The at least one conductive sheet extends out from the shell. The positions of the conductive sheets of the battery devices correspond to the conductive pads of the circuit layout, and the conductive sheets are electrically connected to the conductive pads respectively. 
     In one embodiment, the printed circuit board further delimits a plurality of openings, and the conductive sheets of the battery devices pass through the openings. 
     In one embodiment, the battery cells of each of the battery devices are connected in parallel via the at least one conductive sheet, and the battery devices are connected in series via the conductive sheets. 
     In one embodiment, the battery devices are stacked up, and the battery module further includes at least one stationary lid for fastening the stacked battery devices. 
     In one embodiment, the at least one conductive sheet of each of the battery devices extends along a first direction. The first direction extends toward an interior surface of the at least one stationary lid. The battery devices are stacked up along a second direction, and long axes of the battery cells of each of the battery devices extend along a third direction. 
     In one embodiment, the battery module further includes at least one screw. Each of the battery devices further delimits at least one screw hole, and an opening of the screw hole faces toward the at least one stationary lid. The at least one stationary lid delimits a plurality of through holes. The at least one screw is inserted into a corresponding screw hole by passing through a corresponding through hole. 
     In one embodiment, each of the battery devices further includes at least one convex positioning post, and the at least one convex positioning post protrudes toward the at least one stationary lid. The printed circuit board of the circuit board delimits a plurality of positioning holes for receiving the convex positioning posts respectively. 
     In one embodiment, the circuit board is located between the at least one stationary lid and the battery devices. The first connector of the circuit board faces toward the interior surface of the at least one stationary lid. The interior surface of the at least one stationary lid further delimits a fillister. The first connector of the circuit board and the bus wire are located in the fillister. 
     In one embodiment, the circuit board is located between the at least one stationary lid and the battery devices. The first connector of the circuit board faces toward the interior surface of the at least one stationary lid. The at least one stationary lid further delimits a through groove, and the first connector of the circuit board is located in the through groove and exposed from an exterior side surface of the at least one stationary lid. 
     As mentioned above, in one embodiment, the battery module includes a circuit board and at least one bus wire. The control board is electrically connected to the battery devices or the thermal sensor  512  via the circuit board and at least one bus wire. In one embodiment of the invention, due to the installation of the circuit board, the design of the control board can be simplified and modularized so that only different circuit boards need to be designed for different electrical apparatuses that can operate with the same control board. Furthermore, since most circuitry can be disposed on the circuit board, the connections among the components of the battery module can be simplified. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein: 
         FIG. 1  shows a schematic diagram of a battery module according to one embodiment of the invention. 
         FIG. 2  shows a schematic diagram of a battery device according to one embodiment of the invention. 
         FIG. 3  shows a schematic diagram of a circuit board according to one embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In the following description of the invention, the term “A is coupled to B” or “A is electrically connected to B” refers to A that is coupled or electrically connected to B directly, or that is coupled or electrically connected to B indirectly via a material or a body to thereby make conductive between A and B. Besides, the term “A contacts B” refers to a direct contact or an indirect contact between A and B. 
       FIG. 1  shows a schematic diagram of a battery module according to one embodiment of the invention. As shown in  FIG. 1 , a battery module  100  includes a plurality of battery devices  200 , a circuit board  300 , at least one bus wire  400  and a control board  500 . The control board  500  controls charging and discharging operations of the battery devices  200  via the circuit board  300  and the at least one bus wire  400 . The battery devices  200  are electrically connected to a circuit layout (not shown, referring to  FIG. 3 ) of the circuit board  300  while the at least one bus wire  400  is electrically connected between the circuit layout of the circuit board  300  and the control board  500 , thereby to cause the battery devices to electrically connect with the control board  500 . Such design can prevent from using an excessive amount of wires, simplify the internal structure of the battery module  100  and reduce the manufacturing working hours. The detailed structure according to one embodiment of the invention will be described more specifically as follows. 
       FIG. 2  shows a schematic diagram of a battery device according to one embodiment of the invention. As shown in  FIG. 2 , each battery device  200  includes at least one conductive sheet  220  and a plurality of battery cells  230 . The battery cells  230  are electrically connected via the at least one conductive sheet  220 . In one embodiment, the battery cells  230  are electrically connected in parallel via the at least one conductive sheet  220 . More specifically, the positive electrodes of the battery cells  230  are all coupled to a first conductive sheet  221  while the negative electrodes of the battery cells  230  are all coupled to a second conductive sheet  222 . In one embodiment, each battery device  200  further includes a shell  210 . The battery cells  230  and the conductive sheets  221  and  222  are all disposed inside the shell  210 ; besides, the conductive sheets  221  and  222  extend from the interior of the shell  210  to its exterior (referring to  FIGS. 1 and 3 ). 
     As shown in  FIG. 1 , the bus wire  400  includes a connection wire  420  and two connectors  410   a  and  410   b.  The connection wire  420  is electrically connected between the connectors  410   a  and  410   b.  The connector  410   a  is electrically connected to a connector  320  (referring to  FIG. 3 ) of the circuit board  300  while the connector  410   b  is electrically connected to a connector  510  of the control board  500 . The structure of the connector  510  of the control board  500  fits the structure of the connector  410   b  of the bus wire  400  so that the connector  410   b  can be assembled into the connector  510 . The structures of the connector  510  and the bus wire  400  are well known in the art and can be implemented by existing or yet-to-be developed techniques; therefore, their detailed descriptions are omitted for the sake of brevity. 
       FIG. 3  shows a schematic diagram of a circuit board according to one embodiment of the invention. As shown in  FIG. 3 , the circuit board  300  includes a printed circuit board (PCB)  310 , at least one connector  320  and a circuit layout  330 . The at least one connector  320  and the circuit layout  330  are disposed on the circuit board  310 , and the at least one connector  320  is electrically connected to the circuit layout  330 . The structure of the connector  320  of the circuit board  300  fits the structure of the connector  410   a  of the bus wire  400  so that the connector  410   a  can be assembled into the connector  320 . The structures of the connector  410   a  and the connector  320  are well known in the art and can be implemented by any existing or yet-to-be developed techniques; therefore, their detailed descriptions are omitted for the sake of brevity. 
     The circuit layout  330  disposed inside the PCB  310  includes a plurality of conductive wiring lines  331  and a plurality of conductive pads  332 . The conductive pads  332  are exposed on the surface of the PCB  310  and located at the side edges or the middle part of the PCB  310 . The position of each of the conductive pads  332  corresponds to one of the conductive sheets  220  extending out from the battery devices  200 . The conductive wiring lines  331  are coupled between the conductive pads  332  and the at least one connector  320 . 
     In one embodiment, the extending direction of the conductive sheets  220  forms a predetermined angle with the surface of the PCB  310 , for example 90 degrees. During the manufacturing process, when the conductive sheets  220  are to electrically connect with the corresponding conductive pads  332 , the conductive sheets  220  is bent so that the terminals of the conductive sheets  220  are in parallel with the surface of the PCB  310  to contact the corresponding conductive pads  332 . In a preferred embodiment, the terminals of the conductive sheets  220  are further soldered on the conductive pads  332  to make the connections among the components of the battery module  100  more stable. 
     Besides, in one embodiment, a plurality of openings  390  are delimited in the side edges or the middle part of PCB  310 . The positions of the openings  390  correspond to the conductive pads  332  and the terminals of the conductive sheets  220 . As shown in  FIG. 3 , the terminals of the conductive sheets  220  extend out from the battery devices  200  and pass through the corresponding openings  390 . Meanwhile, the terminals of the conductive sheets  220  are bent in order to contact the conductive pads  332 . Since the openings  390  are able to provide positioning, the procedure of connecting the terminals of the conductive sheets  220  with the conductive pads  332  is simplified. In the embodiment of  FIG. 3 , the openings  390  can be notches (for example, at the side edges of the PCB  310 ). In one embodiment, the openings  390  can also be through holes (for example, in the middle part of the PCB  310 ). 
     In one embodiment, the battery module  100  further includes at least one thermal sensor  512 . The thermal sensor  512  is electrically connected to two conductive wiring lines  331  of the circuit layout  330  via two wires  511  respectively. By such a design, the thermal sensor  512  can provide a thermal signal for the control board  500  via the circuit board  300  and the at least one bus wire  400 . The control board  500  can detect the temperature of the whole battery module  100  according to the thermal signal provided by the thermal sensor  512 . The installation position of the thermal sensor  512  as shown in  FIG. 3  is provided by way of example and not limitation of the invention. In one embodiment, the thermal sensor  512  can be installed at any corner of the battery module  100 , and the two wires  511  are installed in such a manner that the two wires  511  are coupled between the circuit layout  330  and the thermal sensor  512 . Such design can simplify the circuit layout of the control board  500  to easily offer a modularization of the control board  500 . 
     Furthermore, the invention is not limited to any particular connection methods of the battery devices  200  or the battery cells  230 . A serial connection method according to one embodiment of the invention is described in detail as follows. As shown in  FIG. 2 , in one embodiment, the battery device  200  is regarded as an assembly unit to cause the battery cells  230  to connect in parallel. In other words, the positive electrodes of the battery cells  230  are all coupled to the first conductive sheet  221  while the negative electrodes of the battery cells  230  are all coupled to the second conductive sheet  222 . In such a structure, the voltage of the battery device  200  is roughly equal to that of one battery cell  230 . Depending on different electrical requirements of different electrical apparatuses, the voltage of the battery module  100  can be increased by connecting a plurality of battery devices  200  in series by using the conductive sheets  220 . The structures of connecting a plurality of battery devices  200  in series are well known in the art and can be implemented by any existing or yet-to-be developed techniques; therefore, their detailed descriptions are omitted for the sake of brevity. 
     In one embodiment, the conductive sheets  220  of each battery device  200  all extend toward the circuit board  300  to electrically connect with the circuit layout  330  of the circuit board  300  so that it is convenient to assemble the components of the battery devices  200 . More specifically, as shown in  FIGS. 1 and 2 , in each of the battery devices  200  of one embodiment, when the battery cells  230  and the conductive sheets  220  ( 221  and  222 ) are disposed inside the shell  210 , the long axes (the direction from the negative electrode to the positive electrode, or the direction from the positive electrode to the negative electrode) of the battery cells  230  extend along the direction of  03  while the conductive sheets  220  extend along the direction of D 1 . As shown in  FIG. 1 , when the battery devices  200  are stacked up toward the direction of a side edge, the stacked battery devices  200  extend along the direction of D 2 . When the battery devices  200  are stacked up toward the vertical direction, the stacked battery devices  200  extend along the direction of D 3 . 
     In one embodiment, the battery module  100  further includes at least one stationary lid  550 . Take two stationary lids  550  for example. The stacked battery devices  200  are clamped between the two stationary lids  550  to fix the assembly of the stacked battery devices  200  and stabilize the structure. More specifically, as shown in  FIG. 1 , the battery module  100  further includes at least one screw  552 . The battery devices  200  further delimit a screw hole  251  with its opening facing toward the stationary lids  550 . The normal lines of the stationary lids  550  are roughly in parallel to the direction of D 1 . The stationary lids  550  delimit a plurality of through holes  551 . The screw  552  passes through a corresponding through hole  551  and is inserted into a corresponding screw hole  251 . 
     In one embodiment, the battery devices  200  further includes at least one convex positioning post  252 . The convex positioning post  252  protrudes from the battery devices  200  along the direction of D 1 . In one embodiment, the convex positioning post  252  can also delimit the screw hole  251 . The circuit board  300  delimits a plurality of positioning holes  352 . During the manufacturing process, the convex positioning posts  252  of the battery devices  200  can be respectively disposed in the positioning holes  352  of the circuit board  300  so that the battery devices  200  can be fastened in place with the circuit board  300 . In one embodiment, the circuit board  300  is disposed between the battery devices  200  and one stationary lid  550 ; besides, the connector  320  of the circuit board  300  faces toward the interior surface of the stationary lid  550 . In a preferred embodiment, the interior surface of the stationary lid  550  can delimit a fillister  553  to thereby delimit a containing space between the stationary lid  550  and the circuit board  300 . The connector  320  of the circuit board  300  and the bus wire  400  are located in the containing space (or the fillister  553 ). 
     In one embodiment, the fillister  553  is a through groove which passes through the interior and exterior surfaces of the stationary lid  550 . In other words, the stationary lid  550  further delimits a through groove. The connector  320  of the circuit board  300  is located in the through groove and exposed from the outer side surface of the at least one stationary lid  550 . Such design can prevent a situation that the fillister  553  does not have enough containing space to accommodate the connector  320  and the bus wire  400 . 
     In sum, the battery module  100  includes a circuit board  300  and at least one bus wire  400 . The control board  500  is electrically connected to the battery devices  200  or to the thermal sensor  512  through the circuit board  300  and at least one bus wire  400 . In one embodiment of the invention, due to the installation of the circuit board  300 , the design of the control board  500  can be simplified and modularized so that only different circuit boards  300  need to be designed for different electrical apparatuses that can operate with the same control board  500 . Furthermore, since most circuitry can be disposed on the circuit board  300 , the connections among the components of the battery module  100  can be simplified. 
     While certain exemplary embodiments have been described and shown in the accompanying drawings, it is to be understood that such embodiments are merely illustrative of and not restrictive on the broad invention, and that this invention should not be limited to the specific construction and arrangement shown and described, since various other modifications may occur to those ordinary skilled in the art.