Abstract:
A battery set composed of multiple cells is assembled in a way of individual-charge/merged-discharge. The battery set assembled in the way of the present invention can achieve the highest charge efficiency and maintain balance among multiple cells such that the whole battery set has the largest discharge capacity, and the operating life of the battery set is prolonged. The terminal of the charge tip of the battery set assembled in the way of the present invention is a multi-pin charge terminal.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a battery set, and more particularly, to a battery set assembled in a way of individual-charge and merged-discharge. 
         [0003]    2. Description of the Related Art 
         [0004]      FIG. 1  illustrates a way of assembly of a prior art battery set composed of multiple cells. Please refer to  FIG. 1 . In the prior art, multiple cells, for example, cells  111 ,  112 ,  113 ,  114 ,  115 ,  116 , and  117 , are jointly coupled to each other. Circuit board  12 , which serves to control charge and discharge, couples multiple cells  111 ,  112 ,  113 ,  114 ,  115 ,  116 ,  117 , and  118  together. Thus, charge and discharge are both via power cords  131 ,  132 . 
         [0005]    In the prior art, charge and discharge are both via power cords  131 ,  132 . Thus the way of assembly of the battery set tends to bring problems about maintaining balance among multiple cells. Especially when the number of cells goes larger, it becomes more difficult to maintain balance; meanwhile, to select a single cell which meets the requirement of balance becomes more time-consuming. 
         [0006]    Therefore, it is desirable to provide an innovative battery set to mitigate and/or obviate the aforementioned disadvantage. 
       SUMMARY OF THE INVENTION 
       [0007]    The objective of the present invention is to provide an assembly system of a battery set such that the battery set can achieve the highest charge efficiency and maintain balance among multiple cells. 
         [0008]    The present invention is a battery set system assembled in a way of individual-charge/merged-discharge. The terminal of its charge tip is a multi-pin charge terminal, different from a two-pin charge/discharge terminal in the prior art. The system subdivides the internal part of the battery set composed of multiple cells into two or more units. Each unit has a charge circuit for independent charge; the discharge part of each unit is coupled to one another for discharge. 
         [0009]    The present invention is characterized in that: the battery set composed of multiple cells is assembled in a way of individual-charge/merged-discharge. When the battery set composed of multiple cells is being charged, its internal part is subdivided into two or more units. Each unit has a charge circuit for independent charge. When the battery set composed of multiple cells is being discharged, it is done by a way of merged-discharge. The present invention has a capability of charge/discharge protection for the battery set. It is able to monitor an overall voltage of the battery set and a voltage of each cell to prevent over discharging. Moreover, the terminal of its charge tip is a multi-pin charge terminal. 
         [0010]    Preferred embodiments of the invention are defined in the sub-claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is a schematic drawing of a way of assembly of a prior art battery set. 
           [0012]      FIG. 2  is a schematic drawing of an individual-charge and merged-discharge battery set of the present invention. 
           [0013]      FIG. 3  is a comparison drawing of a voltage test of the individual-charge and merged-discharge battery set of the present invention when it is fully charged and after it is discharged. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0014]    The advantages and innovative features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
         [0015]    The way of assembly of a prior art battery set composed of multiple cells is to install multiple cells on a protection circuit board. Then the battery set can be charged and discharged. The way of assembly of an individual-charge and merged-discharge battery set of the present invention is different from that of the prior art battery set composed of multiple cells. The present invention subdivides the internal part of the battery set composed of multiple cells into two or more units. Each unit has a charge circuit for independent charging; the discharge part of each unit is coupled to one another for discharge. Therefore, the battery set of the present invention can be charged individually and are discharged together. 
         [0016]      FIG. 2  is a schematic drawing of the individual-charge and merged-discharge battery set of the present invention. 
         [0017]    Please refer to  FIG. 2 . The individual-charge and merged-discharge battery set of the present invention comprises: discharge circuit board  21 , internal subdivided units  241  and  242 , transmission power cords  261  and  262 , multi-pin charge terminal  23 , output power cords  251  and  252 . The internal subdivided units  241  comprises a circuit board  291  and two cells  221  and  222 ; and the internal subdivided units  242  comprises a circuit board  292  and two cells  223  and  224 . 
         [0018]    Multi-pin charge terminal  23  has several contact pins  231 ,  232 ,  233 ,  234 ,  235 ,  236 , and  237 , able to be connected to internal subdivided units  241  and  242  via transmission power cords  261  and  262 . In one embodiment of the present invention, the multi-pin charge terminal  23  is connected to a power source (not shown) for supplying electrical power to the contact pins  231 ,  232 ,  233 ,  234 ,  235 ,  236 , and  237 . In one embodiment of the present invention, each of the power cords  251 ,  252 ,  261  or  262  is an assembly of two or more electrical conductors (such as a supply wire, a return wire, and a grounding wire), held together with an overall sheath, for transmitting electrical power. 
         [0019]    When the individual-charge and merged-discharge battery set of the present invention is being charged, it is being charged via multi-pin charge terminal  23 . Internal subdivided units  241  and  242  are used as independent charge units. The circuit boards  291  and  292  of the internal subdivided units  241  and  242  monitor the charge of multiple cells  221 ,  222 ,  223 , and  224 . When multiple cells  221 ,  222 ,  223 , and  224  are fully charged, the circuit boards  291  and  292  of the internal subdivided units  241  and  242  discontinue electrical current automatically. When the individual-charge and merged-discharge battery set of the present invention is being discharged, multiple cells  221 ,  222 ,  223 , and  224  are being discharged together via output power cords  251  and  252  of discharge circuit board  21 ; meanwhile, discharge circuit board  21  serves as means for preventing over discharge by monitoring the overall voltage of the battery set and the voltage of each of the multiple cells  221 ,  222 ,  223 , and  224  to avoid over discharging multiple cells  221 ,  222 ,  223 , and  224 . Thus over discharging protection can be achieved. In one embodiment of the present invention, the individual-charge and merged-discharge battery set of the present invention is a lithium-ion battery set. 
         [0020]      FIG. 3  is a comparison drawing of a voltage test of an individual-charge and merged-discharge lithium-ion battery set (36V/10 Ah) when it is fully charged and after it is discharged in accordance with one embodiment of the present invention. The test includes cycling testing 100 times. As shown in  FIG. 3 , the voltages of the battery set when it is fully charged can all reach 42V. This shows that multiple cells  221 ,  222 ,  223 , and  224  of the battery set assembled in the way of the present invention can all get into a balance state in the test. 
         [0021]    It should be noted that the number of cells of the present invention is not limited to the number of multiple cells  221 ,  222 ,  223 , and  224  shown in  FIG. 2 , as long as it is plural. Also, the number of internal subdivided units of the present invention is not limited to the number of internal subdivided units  241  and  242  shown in  FIG. 2 , as long as it is plural. The number of transmission power cords of the present invention depends on the number of internal subdivided units; meanwhile, the number of contact pins of the multi-pin charge terminal also depends on the number of internal subdivided units and is not limited to what is shown in  FIG. 2 . 
         [0022]    It is noted that the above-mentioned embodiments are only for illustration. It is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents. Therefore, it will be apparent to those skilled in the art that various modifications and variations can be made to the battery set of the present invention without departing from the scope or spirit of the invention.