Preface: With the more and more extensive application of lithium battery, there are more and more application requirements. There are unique requirements for the size, space, function and even appearance of lithium battery pack, which makes the customized lithium battery pack become a trend. As a high-tech company driven by technology research and development, CeramiX has accumulated a lot of experience in the research of lithium battery application scenarios. We have a complete lithium battery pack workshop, automatic assembly line, strong technical team, and perfect supply chain, which makes our pack customization has the competitive advantage of high quality and low price. Below we will share the whole process of lithium battery pack customization.

1.Customer requirements

If the customer sends an inquiry, it is best to describe your requirements for a customized lithium battery pack, for example, what size do you want? How many volts and ampere hours? How long do you have to work? Battery pack space? What are the requirements for waterproof and dust-proof level? Custom quantity? Communication protocol requirements? And so on. When the customer gave us all his needs, it is up to us to ask the customer some basic questions, such as the use of what equipment? What is the use environment? Such as the points these customers maybe did not mention.

After a series of discussions to ensure that we fully understand the customer’s needs and detailed requirements, our technical department begins to prepare the technical proposal.

However, the technical solution produced in this link is only a theoretical solution, so that the customer can confirm that it is the product he wants. After the contract is signed and the deposit is paid, our technical department will take time to make a complete detailed drawing and data sheet for the customer to confirm the production

2. Selection of battery cell

Lithium battery custom was popular,the reason is it according to the customer’s demand in certain cases randomly customized shape, size, performance, etc., one of the most important point is to select battery cell, the lithium battery cell at present the use of two of the most widely is the LFP and Ternary lithium, the two battery cell both performance, security, price is different, This is to customers according to their own needs to choose. You can see our previous blog post on cell selection: https://ceramixenergy.com/knowledge-of-lithium-battery-cell/ and https://ceramixenergy.com/how-to-choose-the-most-suitable-lithium-battery-for-you/

If you have any further questions, please contact us at tommyzhao@ceramixenergy.com to answer your questions one-on-one.

3.The quotation

After we know clearly what customer needs, we will quote a relatively accurate price. The price we give to the customer will be based on the battery cell cost selected by the customer according to the demand, plus the production process cost of lithium battery pack, and then the customer will decide whether it is feasible.

Tip: Lithium battery pack customization is mainly for industrial use, so the capacity can not be customized too small, for most lithium battery manufacturers do not customize the capacity of the battery below 10AH.

4.Cell sorting and distribution group

The first step is cell sorting, which is a very rigorous and important step in the customization process of lithium battery pack. If the step is not well done, it is likely to lead to the inconsistency of the cell group, thus affecting the performance of the whole pack. The parameters of the automatic sorting machine should be :(taking large capacity prismatic cell as an example, ternary lithium battery and LFP battery)

Voltage difference 10mV(if the number of cells, strict consistency requirements, you can choose to set 5mV as a first gear);

The internal resistance difference is 5Mω (1-3Mω can be set if the consistency requirement is strict).

The difference of cell capacity can not be screened on the automatic sorting machine, so it is necessary to grade the capacity by the aging cabinet,this is also known as Capacity grading. The cell will be packed and shipped according to the voltage, capacity and internal resistance before leaving the factory. When the cell arrives, our IQC part needs to carry out spot inspection, the capacity difference is suggested to be within 1%. Once again, it is necessary to mention that our battery cells from CALB,REPT,EVE,Woo-power and many other first-line battery manufacturers direct supply, quality is guaranteed, the price has advantages.

5.Lithium battery cell assembly fixture, automatic laser spot welder

When the battery cell is installed, be sure to assemble the cell in the positive and negative order in SOP of PE engineer. The reverse order will cause short circuit of the cell. Set up the automatic laser spot welder program, the jig cell into the start of automatic spot welding.

After the completion of the automatic spot welding, our quality inspection department will carry out a full inspection of the automatic spot welding battery pack. The leakage point and explosion point need to be repaired.

6. Solder PCM/BMS for lithium battery pack

For this step, our CeramiX require that our employees wear electrostatic bracelets to protect the PCM/BMS from electrostatic damage.

There are different steps for different battery pack designs. If it is designed for PCM spot welding of battery pack, no soldering is required. Our quality inspection will also carry out full spot welding inspection of PCM spot welding to battery pack.

If PCM/BMS needs soldering tin, the pack of connecting screws should also be inspected to ensure 100% quality of solder joints and screw joints. Voltage acquisition line, need to follow the sequence B-,B1… In order to B +; Or unplug the voltage acquisition line and insert it and then weld it. After the welding is completed, test the acquisition and insert, and then connect BMS after confirming it is correct.

7. Semi-finished product insulation

Necessary fixation and insulation of voltage collection lines, conductors, positive and negative output lines. The auxiliary materials are high temperature tape, highland barley paper, epoxy board, cable tie and so on. The employees of CeramiX have been trained strictly and professionally before working, and have a strong safety awareness. They will never superimpose compression on the voltage collection wire or output wire of the battery pack, which may easily lead to extrusion damage and short circuit.

8.Semi-finished product testing

After BMS is added to the battery pack, we will conduct a semi-finished product test. The routine test includes: 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 customers have special requirements, we will also arrange high temperature and low temperature test, acupuncture test, drop test, salt spray test, special lithium battery pack test, etc.

In particular, it is necessary to pay attention to the bearing capacity of the battery pack, such as whether the BMS can withstand high voltage when the whole battery is overcharged. Short circuit test whether BMS can withstand instantaneous high voltage and high current; Whether the BMS can withstand pulse current during overcurrent test.

9.Lithium battery pack packaging

This step also decided by the design. But before packing, the signal acquisition line and the positive and negative electrodes of the battery pack must be insulated.

PVC packed battery pack, will be sealed by superheat shrink machine. Ultrasonic sealed battery pack, will be done by the ultrasonic machine. Battery pack with metal outer box, outer box assembled by practised hand. During this process, our employees are extremely careful to handle the battery pack with care to avoid collisions, squeezes and so on. Conductors should be well insulated to avoid short circuit.

10. Whole set of tests

Set the parameters of the whole set of tester, and test the whole set of tester on the battery pack.

Main test items: shipment voltage, internal resistance, simple charge and discharge.

Alternative test items: overcurrent, short circuit

11.Packing and shipping

According to the special foam size box, do not place at will, when the battery pack is transported, the most afraid of the internal packaging has a big gap, must ensure that there is enough foam to buffer, to avoid transportation crash. For the safety of large battery pack, we need to arrange the shipment of wooden frame.

12.Other matters needing attention for export

Certificate of export products, the shipment must be complete, such as MSDS and UN38.3 certificate, our battery cells are big brand, so the basic certification complete, on the basis of the lithium battery pack also need to apply for such certificate, otherwise do not conform to the requirements of the transport, but generally speaking, we can apply for the certificate is finished before shipment, It will take about 10-12 working days to apply for the certificate after the sample is assembled. In addition, if the customer has other certification required for customs clearance in the import country, we need to communicate clearly and make early preparation before the order starts.