Cylindrical lithium battery pack assembly process
Lithium battery has high energy density and is widely used, which is the highest battery production in China, but the production cost of lithium battery is not low, so improving the yield of products is an effective means to reduce the production cost of batteries. In the production process of lithium battery, a number of processes can be added to improve the yield of product products. Among them, putting insulating paper on the electrode between the positive and negative of the lithium battery can effectively reduce the internal short circuit caused by welding the electrode of the battery.
There are two main ways to paste insulating paper:
Method 1: Manual sticker
Method 2:
Automatic stick barley paper machine: artificial cell into the hopper —— wave wheel rotation out of the battery —— belt mobile batteries —— cylinder launch battery team —— battery positioning compression —— stepping battery drive the whole volume of highland barley paper mobile —— cylinder stick barley paper —— waste recycling —— finished battery to the cutting tank —— artificial box (operation parameters can be set according to the actual requirements of the customer)
Cell sorting is for the pursuit of consistency, the consistency difference of cells, just like the mix of old and new batteries. The big difference of the cell, in addition to the drag on the normal cell, or the weak point of the whole battery pack, overcharge, over-put, heat and so on are from their start.
The way in which groups are sorted：
Cell automatic sorter:
The cell into the bin —— test wheel running to the test position —— test cylinder action —— test needle pressure to the cell —— tester reading data —— transmission to the computer —— computer for gear matching —— cell transfer to the sorting belt —— sorting belt running to the specified gear —— gear cylinder action to push the cell.
Method 1:
Manual lithium battery spot welder:
Power supply —— test whether the WELED switch is open —— Place the products on the desktop —— welding pedal —— welding head down —— spot welding completed —— welding head back without leakage
Method 2:
Automatic spot welding machine:
Double-sided automatic spot welding machine:
cell / bracket / battery nickel sheet into the device —— place the device to the induction position —— the equipment automatically spot welding and sent to the feeding position (select
the discharge mode: forward and out, forward and out) —— Take out the battery pack from the device —— for the next production cycle
Single-sided automatic spot welding machine:
cell / bracket / battery nickel loading gear —— placed fixture to the left platform induction position —— equipment automatic spot welding out to the feeding position —— artificial flip gear —— placed to the right platform induction position —— equipment automatic spot welding out to the feeding position —— from the battery —— the next production cycle (left platform work platform can into the product, waiting for the platform welding completed, will automatically turn to the right platform welding. When welding the right platform, the left platform can replace the product and wait for the welding of the right platform, which will automatically transfer to the left platform welding and cycle in turn)
Method 1:
Manual lithium battery spot welder:
Power supply —— test whether the WELED switch is open —— Place the products on the desktop —— welding pedal —— welding head down —— spot welding completed —— welding head back without leakage
Method 2:
Single-sided automatic spot welding machine:
cell / bracket / battery nickel loading gear —— placed fixture to the left platform induction position —— equipment automatic spot welding out to the feeding position —— artificial flip gear —— placed to the right platform induction position —— equipment automatic spot welding out to the feeding position —— from the battery —— the next production cycle (left platform work platform can into the product, waiting for the platform welding completed, will automatically turn to the right platform welding. When welding the right platform, the left platform can replace the product and wait for the welding of the right platform, which will automatically transfer to the left platform welding and cycle in turn)
The voltage acquisition line, wire and negative output line shall be fixed and insulated as necessary. The auxiliary materials are high
temperature tape, highland barley paper, epoxy board, tie, etc. Need to have a safety awareness, do not stack the battery pack voltage
acquisition line or output wire compression, easy to lead to extrusion damage and short circuit.
After the battery pack adds BMS, a semi-finished product test can be carried out. Routine test tests include simple charge and discharge test, whole group internal resistance test, whole group capacity test, whole group overcharge test, whole group overdischarge test, short circuit test and overcurrent test. If there are special requirements, high temperature and low temperature test, acupuncture test, drop test, salt spray test, etc., special lithium battery pack test, destructive, sampling inspection is recommended. Attention should be paid to the bearing capacity of the battery pack, such as whether the BMS can withstand high pressure during the whole overcharge test; whether the BMS can withstand the instantaneous high voltage and high current during the short circuit test; and whether the BMS can withstand the pulse current during the overcurrent test.
This step requires the use of a finished comprehensive tester.
This step, you also need to see the design. But before packaging, the signal acquisition line and the insulation of the positive and negative electrodes of the battery pack must be done well. PVC Packaging battery pack, heat shrinkage machine. Ultrasonic sealing of the battery pack, on the ultrasonic machine. Battery pack with metal outer box for outer box assembly. In this process, it is necessary to pay attention to the battery pack light light, to avoid collision, extrusion, etc. Contraverse should be well insulated to avoid short circuit.
Set the parameters of the whole set of tester, and test the whole set of tester on the battery pack. Main test items: shipping voltage, internal resistance, simple charge and discharge. Alternative test items: overcurrent, short circuit.
According to the size of the open mold foam packing, do not put it at will, the battery pack transportation, the most afraid of empty internal packaging. Be sure to ensure that there is enough foam for the internal buffer, to avoid transport collision. Such as large battery pack PACK, for safety, need to arrange wooden frame shipment.
