21700锂离子电池组（35A、48V、1680瓦）

这是我的原始设计创作的电池组，我个人创造了21700 5Ah或5000毫安LG电池。该阵列是(7)个平行单元，3.7V(标称)等于35安培，并与(13)个其他平行单元串联，产生标称48伏。这21700个电池的容量比普通的(隐藏的)电池高出40% !这个包可以创建为(7 x 13) 35A @ 48V或(13 x 7) 65A @ 25.9V，但所有水平母线将需要适当调整大小和重新定位。所有母线都由标准的10mm宽的铜原料制成，厚度可为1.0mm、1.5mm或2.0mm。一根1.0mm厚× 10mm宽的母线等于(12.73)18awg实心铜线。一根18awg的实心铜线电阻为6.4毫欧姆，所以6.4 /(隐藏).(隐藏)= 0毫欧姆。这是关键的，因为P = I^2 * R和P =(35安培)^2 * 0.0005欧姆= 0.6158瓦特耗散在每英尺的母线。因为有(13)顶至底的杆和(2)端杆，每个约9英寸，总母线长度是15 x 9“=(隐藏)”/(隐藏)” = (hidden).(hidden) ft * 0.6158 Watts = 6.93 Watts (and this is with no contact to contact resistance - the reason usually for welding). However, if only 7 amps are drawn then the power dissipated in the bus bars becomes more manageable at P = (7 amps)^2 * 0.0005 ohms = 0.0245 Watts * 11.25 ft = 0.2756 Watts !! Bear in mind that there are 0.28 watts lost during a 7 amp draw and must be accounted for in your power budget as a parasitic power loss. At 7 amps * 48V = 336 watts, 0.28 watts from the 1mm x 10mm bus bar so you will be losing 0.08% power not so much of a problem. :-b All bus bars use PEM clinch fasteners with part number SL-M3-2ZI for metric M3 screws that are attached to 65mm long standoffs that can be in either round aluminum or round plastic. All batteries are connected thru upper positive (+) PCBs that monitor current and will limit over-current and/or over-temperature conditions for each battery as well as providing an *individual* cell charger. All negative side (-) PCBs also limit over-current and/or over-temperature conditions for each battery as an added measure of protection and to ensure electrode balancing. Circuit design is left for the creativity of the pack designer. The 'sweet spot' for the LG 5Ah 21700 battery is with a current draw of 1 amp, where in the capacity of the battery is really 5,100 Ah (see my LG model for energy dissipation curves). So since there are (7) batteries in parallel and if each draws about 1 amp, a very good usage model is 7 x 1 amp = 7 amps @ 48 volts. This will not cause any excessive internal heating and also prolong the life of the battery. It is also recommended that charging be at the same rate of 1 amp per hour to recharge the battery in about 5 hours. Herein again, fast charging will cause excessive internal heating and reduce battery life. Both discharging and charging at about 1 amp will also reduce any risk of thermal runaway, reducing a fire risk. This equates to a power delivery of 7 amps x 50 volts = 350 watts. Obviously more can be drawn, but will cause other risks. At 10 amps (each delivering 1.43 amps) x 50 volts = 500 watts which may be necessary for some applications, but again a preferably 1 amp recharge rate is better. Overall dimensions are 330mm long x 180mm wide x 83mm tall (13.0" L x 7.1" W x 3.3" H) Also this pack can be stacked with two other packs (total of three) to yield 105 Amps with clearance on the sides for vertical bus bars. Each additional pack is rotated 180 degrees to minimize vertical bus bar length.