The Guide to Lithium Batteries for Electric Vehicles

The production of lithium batteries for electric vehicles is mainly divided into two major steps. One is the manufacturing of lithium batteries, and the other is to connect the lithium batteries one by one in series or parallel to achieve the desired voltage and capacity of the lithium battery pack for electric vehicles. Charge and discharge requirements. Let''s find out together below.

1 Manufacturing of lithium batteries for elctric vehicle lithium batteries. This mainly talks about the production and manufacturing method of lithium battery cells. The basic steps are as follows:

a. Stirring and mixing of raw materials: Mix the electrode active materials, binders, solvents, etc. together, stir and disperse thoroughly, and prepare a slurry.

b. Coating of positive and negative electode sheets: Apply the sluryy intermittently and evenly on the surface of the transmission current collector and dry it to make positive and negative electrode sheet rolls respectively.

c. Cold pressing of positive and negative electrode pieces: After the positive and negative electrode pieces are coated, the positive and negative materials are relatively loose, and a certain amount of pressure needs to be applied to the electrode pieces to compact the positive and negative electrode materieals to a certain range.

d. Cutting into strips: According to the model of the battery, the positive and negative electrode sheets need to be cut into corresponing widths.

e. Stacking of poisitive and negative electrode sheets: Small pieces of positvie and negative electrode sheets and isolation films are stacked to from a bare cell.

f. Case insertion, spot welding, and vacuum drying: Wrap the bare battery core in packaging aluminum foil, and heat-seal the top and sides. In addition, it is baked under high vacuum and high temperature to dry out a small amount of moisture, so that the performance of the lithium battery can be guaranteed.

g. Liquid injection: Add the electolyte into the battery core and completely seal the battery core.

h. Formation: The assembled battery is given a certain current to activate the positive and negative materials inside it. The battery can only be used as a power source after being formed.

i. Capactiy classification: During the manufacturing process, the actual capacity of the battery is inconsistent due to process reasons. Through certain charge and discharge detection, the battery is classified according to capacity.

j. Forming: Do the final processing of the battery core shape.

2. Connect the lithium cells one by one in series or parallel to achieve the desired lithium battery pack for electric vehicles. Electric vehicle lithium battery production: For example, if you want to make your own 48v20ah battery pack, you can buy lithium iron phosphate battery, use 3ah 26650, 16 strings of 7 can achieve 48v20ah, and then buy 16 strings of iron lithium protection board, the control current is normal 6a, maximum 12a, instant 18a is enough. Lithium iron phosphate batteries are the safest and most cycled lithium batteris.

a. Prepare materials, including stainless steel battery box and 60V24AH lithium battery for electric vehicle assembly. The lithium battery must be an electric vehicle power battery.

b. Put 20 lithium batteries in a string, totaling 8 strings.

c. Connect 8 strings of lithium batteries in parallel and use separators and tape to insulate them.

d. Fix with tape and connect the welding protective wire in series.

e. Use heat shrink film to wrpa and insulate the string-welded  lithium batteries, connect them to protective boards, and insulate them to prevent short circuits.

f. Short circuit of lithium batteries is very harmful. After wrapping the lithium battery with beat shrink film the assembly of the electric vehicle lithium battery is completed. Just put it into the electric vehicle.

Things to pay attention to when assembling lithium batteries for electric vehicles:

i. Inspection of assembled electric vehicle lithium batteris. During the process of disassembling the battery, check the quality of all connections. Also check whether the safety holder, charging socket, and electric vehicle lithium battery lead wire contact are normal and reliable, and tighten all connections. Those that need to be replaced should be replaced, and their reliability should be focused on. Those that are unreliable should be replaced.

ii. Installation of assembled electric vehicle lithium batteries. Install electric vehicle lithium batteries according to the instructions in the battery box. In fact, most of the batteries inside the battery box are connected in series. Each battery is connected in series with a copper wire of no less than one square meter and welded with a soldering iron. Finally, there are two output terminals, positive and negative, welded on the two sections of the output socket, be careful not to connect them reversely, and they must correspond to the positive and negative poles on the chrger. Otherwise, the consequences will be serious.

iii. Trial of assembing lithium batteries for electric vehicles. After installin the electric vehicle lithium battery, use a multimeter to measure the battery output port voltage. The actual battery voltage is slightly higher than the standard voltage by 2~5V. If it is normal, it can be put into normal operation.