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Nowadays, Lithium battery packs have a wide range in the application fields. Different fields and application scenarios have different requirements for battery packs, such as Ebike lithium battery, Scooter lithium battery, EV lithium battery, Energy storage lithium battery, etc. Above battery used in different fields will be great different from discharge current to cycle life.  Battery pack customization is a mainstream trend.

What is lithium battery pack customization? Custom-made lithium battery products refer to the requirements of product size, environmental characteristics, performance, equipment power, working time, etc, and according to the different working voltage and the selected material characteristic (LFP cell 3.2V or NCM cell 3.7V), the single cells are connected in series and parallel to satisfy the customer’s different working voltage and capacity, and adding battery management system(BMS), shell to compose the final battery pack.

So what should be considered in this battery pack customize process? How to quickly customize the lithium battery pack in SmartPropel? Today follow us to see!

What are the main parameters of lithium battery pack customization?

1.Confirm the lithium battery application field

Different products and application scenarios have different requirements for battery pack ,and the battery packs used in different products will definitely require different cells.

1)Different discharge rate cells. For example, 0.2C discharge cell, 0.5C discharge cell, 1C discharge cell,2C discharge cell,3C discharge cell, 8C discharge cell, or higher.Normally, High speed electric vehicle has high requirements on the large current discharge cell, and for ESS battery, the 0.2C discharge cell is available.

2)Different material system. Select NCM cell or LFP cell for your project.NCM cell has higher energy density, while LFP cell has higher cycle life.Take 48V 10Ah Ebike lithium battery for example, consider the dimension restrictions, we usually select NCM cell.

3)Different cell types. Select cylindrical cell or polymer pouch cell or prismatic cell for your project. For small project, for example, the 36V 15Ah Ebike lithium battery and 72V 45Ah Scooter lithium battery, we usually use cylindrical cell or polymer pouch cell, which will be more flexible for design and manufacturer. But for large project, such as 72V 200Ah Golf Cart lithium battery pack or 48V 300Ah AGV lithium battery pack, we will consider prismatic cell, which is more stable.

2. Confirm the lithium battery voltage and capacity

Specific lithium battery specifications and styles are conducive to lithium battery manufacturers in product development and design process under smaller category circumstances.

The battery voltage is mainly decided by the equipment motor power. In the same voltage platform, the higher capacity, the larger energy, the longer usage time. Take Scooter battery for example, when the E-scooter motor power is certain, the 72V 60Ah lithium battery is two times driving range than 72V 30Ah lithium battery.

3. Check the battery pack dimension

The size of the lithium battery will greatly influence how much energy storage can the lithium battery pack do. The larger space, the more energy can fill in. For example, a customer wants a 48V 50Ah battery pack for AGV and give us a space dimension. Our engineers should calculate whether the space size enough for the energy or not, then can step to the following process.

If you don’t know the battery size, you can use a tape measure to measure the space length, width, and height in your vehicle. If the shape is special and abnormal,please send us a picture or 3D drawing for reference. That would prevent a very large gap between reality and ideal and ensures the produced battery fit in the electric vehicle well.

4. Check the input and output ports of the battery pack

When the lithium battery pack is used in EV, AGV, etc, some of the battery output ports are the same, some of the battery output ports are irregular, and some of the battery output ports are two wires. In the customized battery market, there are various output modes, so the customized lithium battery must confirm the output mode with the manufacturer.

5. Confirm the rated power and peak power of the motor

The constant discharge current and peak discharge current can be calculated by the rated power and peak power of the motor. That will influence our selection of discharge rate cells, BMS and wires.

6. Confirm the battery pack working environment temperature

For most battery packs, the charge temperature range is 0-45℃, the discharge temperature range is -20-55℃.

For example, if the snowmobile lithium battery pack is used in an extremely low temperature, we should consider adding a heating system, to ensure its normal usage.

7. Confirm the charging time

Chargers with different voltages and currents vary greatly.If the voltage of the battery charger is too low, it may not be able to charge, if the electric vehicle charger voltage is too high there will be a greater security risk.

There are two charging models: fast charge and normal charge. 

After confirming the charging time required, the battery pack manufacturer can provide a set of corresponding charger.

8. Confirm the communication protocol

There are several communication protocols in the market: CAN, RS485, RS232, etc. Confirm the communication protocol for your equipment.

9. Other information Details

Tell us your other battery pack requirements, such as pack case material, battery component, color, discharge current, etc. We will satisfy your requirements if achievable.

Battery Pack Customize Working Process

From the customer’s request to the battery pack delivery, we customize the entire lithium-ion battery pack process generally no longer than 30 days.

Step 1(3-4 days): We list the customer requirements for the battery, conduct a feasibility study with the engineering team, then provide the initial quotation. When both sides reach an agreement on the price, project approval formally.

Step 2(2-4 days): Overall design and assessment of the battery pack.

Step 3(1-2 days): Design verification and assessment.

Step 4(10-15 days): After all the designs are finished and customer finish the payment, the battery pack will be processed and produced.

Step 5 (2-3 days): Functional Modules were tested and adjusted successfully.

Step 6 (1-2 days): Packed and delivered. 

The whole process of lithium-ion batteries was successful within 30 days.

Please attention that lithium battery pack customize may involve the following:

1.Opening Mold Fee

For lithium battery pack customize, we offer free design. Normal the battery pack with metal steel sheet not need to open mold. When the battery case is ABS, sometimes may face opening mold problem. Customer should bear the mold cost first, when reaching a certain purchase quantity, the mold cost will be refunded to the customer as a credit.

2. Certificates

Most customers always ask us if the battery packs have CE or BIS certificates etc. To be honest, for the battery cell, we have a whole set of certificates, for the battery pack, some models we have and some models we do not have.

As you know, battery pack are customization is mainstream in recent years. Even two 72V 100Ah Battery packs may be used in the different application fields, with different sizes, different structures, different charge or discharge current, different ports, different communication protocols, etc. As a battery pack manufacturer, we have such a diversity production line, it’s impossible for us to do certificates for the customized battery pack in advance. If you insist on do the CE certificate, we will support you. It will take 7-21 working days to achieve. At the beginning, you bear the CE certificate fee, when reach a certain purchase quantity, we will refund the CE fee to you.

For our side export and your side import, don’t need a battery pack CE certificate, the battery cell certificate is enough. Due to battery cell production went through chemical reactions. For battery pack, just assemble the battery cell, series and parallel the cells, add BMS and sheet. We can arrange freight forwarder. The battery pack will be delivered to your place smoothly.

The above is SmartPropel sharing “How to quickly customize lithium battery pack”. SmartPropel specializing in the research and development of l lithium batteries, service enterprise customers in Europe and the United States, Southeast Asia and domestic. Professional in the R & D proposal, consultation, assembling, testing, and after-sales service to bring the user the latest, the most appropriate service.

1. Different types of products can not be mixed-use, battery structure, chemical composition, battery performance deviation will lead to a serious potential safety hazard.

2. Different batches of products should not be mixed-use, affect the consistency between the individual battery cell. The products of the same batch are those from the same mixing process, with the same chemical composition and with the closest consistency between the cell monomers.

3. The battery must have the necessary temperature control conditions during the use process, lithium battery electrode isolation material is organic plastic products, must not exceed the environment temperature limit.

4. Batteries higher than 36V belong to the high-voltage systems, must be operated in accordance with the high-voltage electrical appliances operating procedures, beware of electric shock.

5. Should not be used over-charge and over-discharge frequently, charging voltage can not be higher than the battery upper limit voltage, or explosion-proof valve open may burst in a serious situation. Discharge voltage can not be lower than the battery lower limit voltage, affecting the battery cycle life.

6. The lithium battery can not be short-circuited use (any kind of battery can not be short-circuited use), can not allow the battery positive and negative pole short-circuited directly. The consequence is that the explosion-proof valve opens, burst when it is serious.

7. For products with lithium battery structure, the specifications must indicate the usage conditions and attention points of lithium battery products.

The price of lithium battery is mainly composed by 3 main accessories: Battery Cell, Protective Board and the Battery Case. At the same time, due to appliances power consumption and electric current, cell connectors material selection (conventional nickel piece, formed nickel piece, copper-nickel composite piece, straddle piece, etc.) will affect the cost. Different connectors (such as aviation plug, from more than 2 dollars to thousands of dollars) may have a greater impact on the cost. Also, different pack process will affect the cost.

1. Cell Selection

Firstly, the selection of cell type with different material systems will affect the total lithium battery price. According to the different cathode materials, lithium battery will have lithium manganate (3.6 v) , Lithium Cobalt (3.7 v / 3.8 v) , lithium nickel cobalt manganate (commonly known as Ternary, 3.6 v) , Lithium Iron Phosphate (3.2 v) , Lithium Titanate (2.3 v / 2.4 v) and other materials system of cells. Regarding the different material system, their voltage platform, safety situation, cycle life, energy density ratio, working temperature are different.

Secondly, the prices of different brand battery cells will be a great difference. The total price gradient can be divided into: Special Cell (including ultra-low temperature, ultra-high temperature, ultra-high multiplying power, abnormal shape) , Japanese Cell (Panasonic, Sanyo, Sony) , Korean Cell (Samsung, LG) , Domestic cell (domestic cell can be divided into first Level( CATL, BYD, ATL) , second level, even five, six levels) . The cells with the same material system but different brands, prices difference can be very large, and through the market competition, the cell quality (safety, consistency, stability) is basically proportional to the price.

2. PCM Demands and Design

PCM designs can be divided into Basic Protection, communication, and BMS

Basic protection: The basic protection includes over-charge, over-discharge, over-current and short-circuits protection, which can be increased heating protection according to production demands.

Communication: Communication Protocol can be divided into I2C, RS485, RS232, CANbus, HDQ, SMBUS, etc. There is simply power display by power meter LED instructions.

BMS: BMS is the first acronym of the battery management system, called Battery Management System, mainly for intelligent management and maintenance of each battery unit, to prevent the battery from over-charge and over-discharge, extend battery life and monitor battery status. Its main functions include battery physical parameters real-time monitor; battery state estimation; on-line diagnosis and early warning; charge, discharge; pre-charge control; balance management and thermal management. This system is mostly used in the electric vehicle battery.

3. Case Demand and Design

Lithium battery case design can be divided into PVC heat seal, plastic, metal.

PVC Heat Seal: Battery Pack external shell packaging form, mainly depends on the customer’s product specific demands. For the PVC heat seal packaging form, generally applicable to the number of cells series or parallel not much, and the overall weight is lower (≤2 kg). However, for batteries with an overall weight of more than 1 kg, it is necessary to add a fixed bracket between the cells and a glass fibreboard around the battery before applying PVC heat seal.

Plastic: Plastic Shell may need to make the mold, mold cost is not a small amount. When pre-development, product unshaped, you can use the hand made shell ( the hand made shell strength is not as strong as mold shell), Shell material and technology (especially with other requirements), will also affect the cost.

Metal: Metal Shell is the same as plastic shell, it is recommended to use sheet metal to make the sample if the product is not shaped or the quantity is not much. In this way, the delivery period is short. For the large batch, it is also recommended to open mold. Also, metal shell waterproof level requirements and special material requirements will greatly affect the cost.

The cost of lithium battery is mainly composed of the battery cell, PCM, structural components, plus enterprise PACK costs, aging costs, management costs and so on. At the same time, due to the technical difficulties, procurement volume, defective rate, lithium battery prices will vary greatly!