What You Need to Know before Designing Your Lithium Battery？

You have decided to make the jump to LiFePO4 batteries, and we could not be more excited. At Battle Born Batteries, we understand this decision can be a big one and comes with a lot of questions. Rest assured, we have got you covered when it comes to what you should keep in mind when purchasing batteries.

Before buying our batteries, it is important to know whether they are right for your setup. Whether it is a charger for a boat, a converter for an RV, or another application, at DNK Lithium Batteries our sales and tech team know of and have tested market. In order to make the buying process easier we have had our team create ups on these in the form of a guide that gives you the parameters of any devices you may be interested in, to ensure they work well with our batteries. We can say with pride that 99% of the devices out there will function with our batteries.

1.Voltage

2.Capacity

3.Current

Your current also plays a role in how much capacity you need. If your application requires a higher current, you will need a larger battery with greater capacity. Remember, your battery must be able to handle peak load current as well as your average current. Engineers often forget to factor in current when they design a custom battery. This is why it’s helpful to have a lithium-ion technology expert guiding you through the battery design process.

4.Battery Cell (cylindrical battery cell[like 18650 21700 26650], prismatic Cell [lipo and lifepo4 cell], Pouch celllike Li-Po 103450)

5.PCM or BMS : it’s used for battery management, common functions like short-circuit protection, over-charge protection, over-discharge protection, over-current protection, NTC.  Monitor battery status like SOC[State of charge], SOH[State of health], SOP[State of power],  Communication with the battery with CAN protocol. When designing a lithium battery pack for your device, you must have two levels of protection. The primary protection should be from the device for charge and discharge of the battery. The secondary protection is from the battery’s protection circuit board which protects batteries from over-charge, over-discharge and short circuit. You must not rely on battery’s PCB/PCM protection only. Let’s use Lithium-ion cells as an example:

• Primary protection: When designing protection on device, the charge circuit should be cut off at 4.2V/cell and discharge circuit should be cut off at 2.5V -3V/cell (please refer to cell’s specification).
• Secondary protection: When designing a protection circuit board (PCB/PCM), the over-charge threshold voltage should not exceed 4.35V/cell and the over-discharge threshold voltage should not below 2.3V/cell.
• Please also consider using a thermistor to monitor the temperature, thermostat to cut off at high temperature and poly-switch to limit the current when necessary.

6.Battery Enclosure: the enclosure could be PVC wrapped, plastic enclosure or metal enclosure. PVC is the most commonly seen type enclosure as it almost doesn’t require any MOQ.

7.Connector: the connector is a very important part of a battery pack although it’s not the top concern. Some connectors are still the expensive expense of the total battery cost.

8.Ensure the Space of Your Application

During normal discharge cycles, your product’s battery needs a little extra room to breathe. You should also plan for extra space in your design in case you need a slightly larger battery to increase run time.

You may want to collaborate with your battery maker as you design your application. Asking the right questions up front about how much space you need helps to prevent mistakes such as leaving too little room for your lithium-ion battery.

9.Choose An Expert Battery Manufacturer

Before you decide on a provider to create your custom solution, schedule a battery consultation to make sure your provider is an expert. Your consultant must be knowledgeable about the facts on lithium. If you have a question your consultant is unable to answer, they should at the very least be able to direct you to the right resources.

Your provider should also offer guidance on whether LiFePO4 or other lithium chemistry are more suited to your application. While LiFePO4 has the highest cycle life, other chemistry have more energy density per cubic inch. This is a strategic decision you must make, and the right battery provider is able to help.

Most importantly, you should receive the highest level of service from your provider. Designing a custom lithium-ion battery is an investment, so your battery maker must be willing to go the extra mile to ensure your solution is the perfect fit.