Battery series after the parallel and series parallel before first analysis of the differentiation

Source: 2020 - 04 - 12 21:07 hits: battery series parallel and series of parallel before the differential analysis of lithium ion battery in the application of the national economy is more and more widely, but its energy and energy are incompatible. In the actual design, often require the user to choose between the battery power and energy and balance, battery designers stuck in a dilemma. In addition, a large composite battery need multiple series can be achieved. Usually according to the theory of the combination of the individual involved in the performance of the battery consistency should be controlled within a narrow range, otherwise the performance difference of single battery in the battery pack will seriously affect the cycle life of battery. As a result, the battery pack need to battery, the more the more difficult to match, and matching the more batteries, will cause enormous waste. In order to solve the above problems, this article on the basis of theoretical analysis for the bold breakthrough, different types of batteries are combined according to certain rules. The experiment proved that this kind of battery combination can not only solve the contradiction between high power and high energy, but also can put forward the specific methods to relieve the pressure on large-scale battery combination. Combination of battery with the same voltage platform ( The positive and negative of the battery material is the same) , that is, V1 V2 = = = = V Vm; Each group a series of battery according to the parameters such as capacity, internal resistance to decorate, namely Bm1 Bm2, Bmn requires each union ( Namely, B1n, B2n,) Between the performance of the match. Consistency between Bmn does not require electrical parameters. I = ( vm - 副总裁) / Rm, in the process of discharge, the resistance value in each cell of the current string is inversely proportional to, that is to say, in the process of discharge, because of the series resistance of each battery string is different, is different from the current through the battery string, that is to say, I1, I2Im is different, in the process of discharge is constantly changing, but the total Ip = I1 + I2 + I3 + + in a dynamic balance. Vp = Vm - ImRm, if in the course of the discharge voltage of the battery, Vm) With all the low ( And other series and battery voltage ratio) Because I = ( Vm - 副总裁) / Rm, the battery will automatically reduce the list of current and battery, it will improve the total voltage and battery string ( Vm) , so the discharge of the battery pack is in dynamic equilibrium state, keep the battery pack must balance voltage ( Vice President) So the battery pack in the voltage in the process of dynamic balance, make each battery string along with all the energy release their capacity, and will not put. The charging process is on the contrary, the principle of which is similar. Due to the charging voltage is dynamic balance, each cell can be filled to capacity, and there will be no charge. After parallel series connection as shown in figure 2. B1n chosen by configuration group, its performance is consistent, namely from the performance perspective, the same B1n B11, B12, same Bm1, same Bm2BmnB union union 2 = 1 = B = B and n ( The B and n as B1n, B2n bone mineral density of the parallel results) 。 Then, a complete set of the battery is equal to the union 1 B, after screening matching union B 2 B and n series, there is no problem to charge and discharge. Bm1 and Bm2Bmn parallel is similar to the analysis of figure 1. Based on the above analysis shows that after the first parallel series battery can charge and discharge normally. Through the above theoretical analysis, which can be concluded that if meet the conditions: all cells form the positive and negative electrode materials of battery voltage platform ( The battery) , series direction corresponding to the set of monomer battery through strict screening ( Maintain internal resistance, capacity, etc. ) Before, then the monomer battery series, before and after the combination of string, consisting of the battery can charge and discharge, generally will not affect the cycle life of the battery pack.