Battery pack protection circuit module
A secondary battery pack comprises a battery and a protection circuit module (PCM), a pair of electrodes of the battery being connected to a protection circuit board (PCB) forming part of the PCM such that the electrode connections are located on a face of the PCB other than a major face that receives PCM components thereon. In some embodiments, the PCM components are mounted on one of a pair of major faces of the PCB, the electrode connections being located on the opposite one of the major faces. In other embodiments, the electrode connections are located on a peripheral edge face that extends transversely between the pair of major outer faces of the PCB. The spatial arrangement of the electrode connections and the PCM components on the PCB is such that substantially the entirety of one major outer face of the PCB is available for the placement of PCM components.
1 . A battery pack comprising:
a pair of electrochemical batteries for generating electrical power, each battery being an elongate modular unit having a lengthwise direction, the pair of batteries being arranged end-to-end in the lengthwise direction with a longitudinal gap between adjacent ends of the batteries;
a protective circuit board (PCB) having a pair of parallel major surfaces that define a first face and a second face on opposite sides of the PCB respectively, a peripheral edge face of the PCB extending transversely between the first and second faces, the PCB being positioned within the longitudinal gap between the batteries and oriented such that the first face and the second face are transverse to the lengthwise direction of the batteries, the first face facing toward one of the pair of batteries and the second face facing toward the other one of the pair of batteries;
a protection circuit module (PCM) comprising PCM components mounted on at least one of the first face and the second face of the PCB, the PCM components and PCB together being configured to control one or more functions of the pair of batteries, each PCM component being an electronic component mounted on the PCB such as to be electrically coupled to circuitry of the PCB; and
an electrode arrangement that connects the pair of batteries to the PCB, wherein respective electrode connections for both of the pair of batteries are located at the first face of the PCB.
2 . The battery pack of claim 1 , wherein the second face of the PCB is free of any electrode connection.
3 . The battery pack of claim 2 , wherein in spatial arrangement of the PCB relative to the electrode arrangement is such that substantially the entirety of the second face is available for mounting of PCM components uninterrupted by the electrode arrangement.
4 . The battery pack of claim 1 , wherein the electrode arrangement comprises four electrode tabs provided by a respective pair of electrode tabs for each of the pair of batteries, all four of the electrode tabs being conductively connected to the first face.
5 . The battery pack of claim 4 , wherein the pairs of electrode tabs are connected to the PCB in a stacked configuration in which respective end portions of a first pair of electrode tabs lie flat against the first face of the PCB, and respective end portions of a second pair of electrode tabs lie flat against the corresponding end portions of the first pair of electrode tabs, such that the second pair of electrode tabs are indirectly coupled to the PCB via the first pair of electrode tabs, to which the second pair of electrode tabs are directly coupled.
6 . The battery pack of claim 5 , wherein the first face of the PCB provides a pair of exposed metal connection pads,
wherein respective front surfaces of the first pair of electrode tabs are soldered or welded to the pair of connection pads, substantially covering the connection pads, respective rear surfaces of the first pair of electrode tabs facing away from the PCB; and
wherein the second pair of electrode tabs are soldered or welded to the rear surfaces of the first pair of electrode tabs.
7 . The battery pack of claim 5 , wherein each electrode tab comprises:
a main portion projecting away from the respective battery towards the PCB, the main portion of each electrode tab extending transversely relative to the first face of the PCB; and
a respective end portion that is bent normally from the main portion to be parallel with the first face of the PCB, to which it is connected.
8 . The battery pack of claim 7 , wherein:
the main portions of the electrode tabs of one of the pair of batteries extend from the respective battery, past the edge face of the PCB and onto the first face of the PCB, and
wherein the main portions of the electrode tabs of the other one of the pair of batteries extend between their battery and the first face of the PCB without extending past the PCB edge face.
9 . The battery pack of claim 5 , wherein the PCM components mounted on the first face are arranged in three sub-blocks interrupted by the two pairs of stacked electrode end portion connections.
10 . The battery pack of claim 4 , wherein the PCM is located within the longitudinal gap between the pair of batteries.
11 . The battery pack of claim 2 , wherein the electrode arrangement includes a pair of electrode tabs extending from one of the pair of batteries, each electrode tab of said pair comprising:
a main portion projecting away from the respective battery in the lengthwise direction, the main portion extending from the second face side of the PCB, past the peripheral edge face of the PCB; and
an end portion that is bent from the main portion to lie flat against the first face of the PCB, such that the end portion is connected to the PCB at the first face on a side of the PCB that is directed away from the battery from which said pair of electrode tabs projects.