Battery pack, tool battery and battery operated tool

Abstract

A lithium-polymer based battery pack for power a hand held power tool or a garden tool, the battery pack has a plurality of battery cells located within housing that is selectively connectable to and supportable by a hand held power tool or a garden tool. The battery cells have a lithium-polymer based chemistry and a nominal charged internal impedance of less than or equal to approximately 5 milliohms. In one embodiment the cells are think cells are stacked within the housing such that each sell is layered over or under an adjacent cell and a resiliently deformable substrate located between adjacent battery cells. In another embodiment the cells may be interconnected to have a combined output voltage of at least 9 volts and to produce a combined average discharge current of greater than 20 amps. A lithium-polymer tool battery and a battery powered tool are also part of the invention.

1 . A lithium-polymer based battery pack for powering a hand held power tool or a garden tool, the battery pack comprising:
 a housing selectively connectable to and supportable by a hand held power tool or a garden tool,   a battery cell located within the housing, the cell having an output voltage of at least 4 volts and producing an average discharge current of greater than 10 amps, wherein the battery cell has a lithium-polymer based chemistry and a nominal charged internal impedance of less than or equal to approximately 10 milliohms.   
     
     
         2 . The lithium-polymer based battery pack of  claim 1  further comprising a plurality of the battery cells located within the housing, the plurality of cells being interconnected to have a combined output voltage of at least 4 volts and a combined average discharge current of greater than 10 amps, wherein each cell has a lithium-polymer based chemistry and a nominal charged internal impedance of less than or equal to approximately 10 milliohms. 
     
     
         3 . The lithium-polymer based battery pack of  claim 2  wherein the plurality of the battery cells comprises between 2 and 20 cells interconnected in series. 
     
     
         4 . The lithium-polymer based battery pack of  claim 2  wherein the plurality of the battery cells comprises between 2 and 10 cells interconnected in series. 
     
     
         5 . The lithium-polymer based battery pack of  claim 2  wherein the plurality of the battery cells comprises between 3 and 5 cells interconnected in series. 
     
     
         6 . The lithium-polymer based battery pack of  claim 1  wherein the battery cell has a nominal amp-hour capacity of greater than 1.5 amp-hours. 
     
     
         7 . The lithium-polymer based battery pack of  claim 1  wherein the battery cell has a nominal cell voltage of between 2 volts and 4.2 volts. 
     
     
         8 . The lithium-polymer based battery pack of  claim 2  wherein the battery cells have a combined output voltage of between 4 volts and 40 volts. 
     
     
         9 . The lithium-polymer based battery pack of  claim 1  wherein the battery cell comprises an anode electrode sheet, a cathode electrode sheet and a lithium-polymer based substrate lamented between the anode and cathode electrode sheets. 
     
     
         10 . The lithium-polymer based battery pack of  claim 1  wherein the battery cell is generally flat and has a cell width and a cell thickness, the cell thickness being less than 15% of the cell width. 
     
     
         11 . The lithium-polymer based battery pack of  claim 2  wherein the plurality of battery cells are layered within the housing such that each cell is lying adjacent another one of the cells, and further including a resiliently deformable substrate between the adjacent cells. 
     
     
         12 . The lithium-polymer based battery pack of  claim 11  wherein a distance between the adjacent cells in greater than 5% of the cell width. 
     
     
         13 . The lithium-polymer based battery pack of  claim 11  wherein the resiliently deformable substrate is thermally conductive or contains a thermally conductive component. 
     
     
         14 . The lithium-polymer based battery pack of  claim 11  including at least one sensor element located between at least two adjacent ones of the cells, said sensor element providing a sensor signal to a battery controller. 
     
     
         15 . The lithium-polymer based battery pack of  claim 14  wherein the sensor element comprises a temperature sensor. 
     
     
         16 . The lithium-polymer based battery pack of  claim 14  wherein the sensor element comprises a temperature sensor, and wherein a second pressure sensing element is located between at least two adjacent ones of the cells and provides a pressure sensor signal to a battery controller 
     
     
         17 . The lithium-polymer based battery pack of  claim 2  wherein the housing defines a housing volume and the plurality of cells provides a combined battery volume, and wherein a ratio of the combined battery volume to the housing volume is greater than 80%. 
     
     
         18 . The lithium-polymer based battery pack of  claim 2  wherein each of the battery cells comprises a first connection lead connected with an anode sheet of the cell and a second connection lead connected with a cathode sheet of the cell, the first connection lead extending from a first edge of the cell and the second connection lead extending from a second edge of the cell, the second edge being a different edge to the first edge of the cell. 
     
     
         19 . The lithium-polymer based battery pack of  claim 18  wherein the second edge is symmetrically opposite the first edge. 
     
     
         20 . The lithium-polymer based battery pack of  claim 18  wherein the plurality of battery cells is stacked within the housing such that each cell is lying adjacent another one of the cells, at least one of the connection leads joined with a connection lead of an adjacent cell. 
     
     
         21 . The lithium-polymer based battery pack of  claim 20  further including a guide member having a convex guiding surface abutting the joined connection leads extending between adjusted cells. 
     
     
         22 . The lithium-polymer based battery pack of  claim 21  wherein the guide member supports the joined connection leads about a smooth radius between the adjusted cells. 
     
     
         23 . The lithium-polymer based battery pack of  claim 21  further including a resiliently deformable substrate between adjacent cells. 
     
     
         24 . The lithium-polymer based battery pack of  claim 23  wherein the guide member and resiliently deformable substrate between adjacent cells is a single integral member. 
     
     
         25 . The lithium-polymer based battery pack of  claim 2  wherein the plurality of battery cells are supported within the housing in a resiliently deformable cradle surrounding at least a part of each cell. 
     
     
         26 . The lithium-polymer based battery pack of  claim 25  wherein the resiliently deformable cradle comprises two or more resiliently deformable members each abutting at least one battery cell. 
     
     
         27 .- 31 . (canceled)