What Information Do You Need to Customize a Lithium Battery Pack?

A custom lithium battery pack is more than simply connecting several battery cells together. It is a complete power solution designed around your device's electrical, mechanical, environmental, and safety requirements.

Whether you are developing a medical device, IoT product, industrial equipment, power tool, wearable device, or energy storage system, providing the right information at the beginning of a battery project can significantly improve development efficiency and help your battery manufacturer deliver a solution that fits your application.

So, what information do you need to prepare when requesting a custom lithium battery pack?

Here are the key specifications your battery manufacturer will typically need.

1. Battery Application

The first thing your battery manufacturer needs to know is what the battery will be used for.

For example:

• Medical devices
• IoT and smart devices
• Industrial equipment
• Power tools
• Golf Cart
• Wearable electronics
• Portable equipment
• Emergency lighting
• Solar energy storage
• Telecommunications equipment

The application provides important context for the entire battery design.

A battery for a wearable device may need to be extremely compact and lightweight, while an industrial battery pack may prioritize high discharge current, durability, temperature resistance, and long cycle life.

Therefore, the more information you can provide about your application, the easier it is for engineers to recommend the right battery solution.

2. Required Battery Voltage

Voltage is one of the most important specifications for a custom battery pack.

Please provide the required operating voltage of your device or system, such as:

3.7V/7.4V/11.1V/12V/14.8V/24V/36V/48V/60V/72V

For lithium batteries, the nominal voltage and maximum charging voltage are not necessarily the same.

For example, a typical Li-ion cell has a nominal voltage of around 3.6V or 3.7V, while a LiFePO4 cell has a nominal voltage of around 3.2V.

The required system voltage determines how cells should be connected in series and is therefore an important starting point for battery pack design.

3. Required Battery Capacity

Next, you need to determine how much energy your application requires.

Battery capacity is usually expressed in:

• mAh (milliamp-hours)
• Ah (amp-hours)

For example: 40mAh / 2,000mAh / 5,000mAh / 10Ah / 50Ah / 100Ah /600Ah

Capacity directly affects the expected operating time of your device.

A simple estimation is:

Required Energy ≈ Power Consumption × Operating Time

For example, if a device consumes 10W and needs to operate for approximately 8 hours:

10W × 8h = 80Wh

However, the actual battery capacity may need to be higher after considering conversion efficiency, discharge limits, temperature, battery aging, and other application conditions.

This is why a battery manufacturer should evaluate the complete application rather than simply matching a requested capacity.

4. Maximum Discharge Current

Battery capacity alone does not tell us whether a battery can safely power your device.Your manufacturer also needs to know the required discharge current.

Please provide:

• Continuous discharge current
• Peak dischargecurrentand Duration of peak current

For example, a device may normally consume 5A but require 15A for several seconds during startup.

This information can significantly affect cell selection, the number of cells connected in parallel, BMS specifications, wiring, connectors, and thermal design.

A battery with a large capacity is not necessarily capable of delivering a high discharge current.

5. Charging Requirements

If you are developing a rechargeable battery pack, charging requirements are equally important.

Useful information includes:

• Charging voltageStandard charging current
• Maximum charging current
• Required charging time
• Charger specifications
• Fast-charging requirements

For example, if your product requires fast charging, the battery cells, BMS, charger, connector, and thermal design all need to be evaluated together.

Providing the charger model or charging specifications can therefore help engineers design a more compatible battery solution.

6. Battery Dimensions and Weight

For many custom battery projects, physical space is just as important as electrical specifications. Please provide the maximum available:

Length × Width × Height

If possible, also provide:

• Maximum battery weight
• Available installation space
• Mounting points
• Screw-hole locations
• Cable exit position
• Required battery shape
• Housing or enclosure requirements(Aluminum/Plastic/Metal/Blue PVC)

A battery may meet the required voltage and capacity but still be unsuitable if it cannot physically fit inside the device.

If you have a mechanical drawing, 3D model, or existing battery sample, providing it to the manufacturer can make the design process much more efficient.

7. Connector, Wire and Cable Requirements

The battery pack may need to connect directly to your device, charger, or control system. Therefore, please specify:

• Connector/Terminal type
• Wire length
• Wire gauge

If you already use a specific connector in your product, providing the connector part number or drawing can help avoid compatibility problems during the prototype stage.

8. Operating and Storage Temperature

Temperature can have a significant effect on battery performance, safety, charging, and service life. Please provide the expected:

• Operating temperature range
• Charging temperature range
• Storage temperature range
• Maximum and minimum environmental temperatures

Some applications may require batteries capable of operating in particularly hot or cold environments.

If your product will be used outdoors, in vehicles, industrial environments, or other demanding conditions, temperature requirements should be identified early in the project.

9. Battery Chemistry

If you already have a preferred battery chemistry, let your manufacturer know.

Common rechargeable lithium battery chemistries include:

• Lithium-ion
• Lithium-polymer
• LiFePO4
• Ni-MH
• Ni-CD
• Li-SOCI₂

 

Different chemistries have different characteristics in terms of:

• Energy density
• Safety
• Cycle life
• Discharge performance
• Operating temperature
• Size and weight
• Cost

However, if you are not sure which chemistry is appropriate, you do not necessarily need to make the decision yourself.

A professional battery manufacturer can evaluate your application's requirements and recommend a suitable chemistry and cell type.

10. BMS Requirements

For many lithium battery packs, the Battery Management System (BMS) is an essential part of the design. Depending on the application, you may require functions such as:

• Overcharge protection
• Over-discharge protection
• Overcurrent protection
• Short-circuit protection
• Temperature protection
• Cell balancing
• State-of-charge monitoring
• Battery communication

You should also specify whether the battery needs to communicate with your device or control system. For advanced applications, communication interfaces may include:

• SMBus
• I²C
• UART
• RS485
• CAN

The BMS should be designed around the battery configuration and the requirements of the complete system rather than selected separately at the end of the project.

11. Required Certifications

Certification requirements depend on the battery type, application, and target market. Depending on your project, you may need standards or certifications such as: UN38.3 / IEC 62133 /UL1642 /UL2054 /CE /CB /RoHS /KC /BIS /PSE /MSDS /Other market-specific requirements

It is important to identify certification requirements early because they can affect cell selection, BMS design, mechanical construction, testing, documentation, and development schedules.

Howell Energy provides battery products and customized solutions with a range of international certifications and market-specific compliance support.

12. Other Special Requirements

Finally, tell your battery manufacturer about anything else that may affect the design. For example:

• Waterproofing requirements
• Dust resistance
• Vibration resistance
• Shock resistance
• High/Low-temperature operation
• High discharge rate
• Long cycle life
• Lightweight design
• Ultra-thin design
• Special enclosure
• Custom labeling(OEM/ODM)
• Communication requirements
• Special packaging
• Target production quantity
• Expected delivery schedule

Even a small requirement can sometimes have a major impact on battery design.It is always better to discuss these requirements at the beginning of the project rather than after the prototype has already been developed.

What Happens After You Provide These Specifications?

Once your requirements are available, a professional battery manufacturer can begin evaluating the project. A typical custom battery development process may include:

Step 1: Requirement Analysis

Engineers review the electrical, mechanical, environmental, and regulatory requirements of the application.

Step 2: Cell Selection and Battery Design

Suitable cells and battery configurations are evaluated based on voltage, capacity, discharge performance, dimensions, cycle life, and other requirements.

Step 3: BMS and Protection Design

The BMS, protection functions, communication interface, wiring, and other electrical components are designed according to the battery pack requirements.

Step 4: Prototype Development and Testing

A prototype battery pack is produced for electrical, mechanical, thermal, and functional verification.

Depending on the application, testing may include capacity testing, cycle testing, temperature testing, vibration testing, safety testing, and other reliability evaluations.

Step 5: Certification and Validation

If required, the battery pack can proceed through the appropriate certification and compliance process for the target market.

Step 6: Mass Production

After the design has been validated and approved, the battery pack can move into mass production with quality control throughout the manufacturing process.

What If You Don't Know All the Specifications?

This is actually very common.

Many customers who contact a battery manufacturer do not have a complete battery specification yet.

You may only know:

“We need a rechargeable battery for our device.”

That's okay.

At the beginning of a project, you can provide as much information as you currently have, such as:

• Product application
• Device power consumption
• Expected operating time
• Available battery space
• Maximum current
• Target market
• Product drawings or photos
• Existing battery specifications
• Annual purchasing volume

A professional battery engineering team can use this information to help determine the appropriate battery chemistry, voltage, capacity, cell configuration, BMS, connector, and mechanical design.

Custom Battery Solutions from Howell Energy

Howell Energy is a battery manufacturer with more than 20 years of experience in the battery industry. We provide OEM/ODM battery solutions covering battery design, cell selection, pack development, BMS integration, testing, and customized requirements.

Our custom battery capabilities include different voltage and capacity configurations, customized dimensions and shapes, connectors, communication interfaces such as RS485 and CAN, and other application-specific requirements.

Our battery portfolio includes Li-ion, Li-polymer, LiFePO4, lithium primary, NiMH, Ni-Cd, and customized battery packs, allowing us to recommend different battery technologies according to the application.

Ready to Develop Your Custom Battery Pack?

You don't need to have every specification finalized before contacting us.

Send us the information you already have — including your application, required voltage and capacity, dimensions, current requirements, operating environment, and any drawings or existing battery samples.

Our engineering team can evaluate your requirements and help turn your product concept into a practical battery solution.

Howell Energy — Your Reliable Battery Partner.