Overview
We will be building a 100Ah LiFePO4 battery using cell modules we purchased from BatteryHookup.com.
Parts
| Part | Qty | Picture | URL |
|---|---|---|---|
| 3.2V 100ah MODULES | 4 |
| https://web.archive.org/web/20210516124542/https://batteryhookup.com/products/new-battery-hookup-lifep04-32650-3-2v-5000mah-cells-1 |
| 100A Smart LiFePO4 4S BMS | 1 |
| https://batteryhookup.com/products/12v-lifepo4-smart-bms-w-low-temp-cutoff |
| 50-Cal Black Ammo Box with Tray | 1 |
| https://www.princessauto.com/en/50-cal-black-ammo-box-with-tray/product/PA0008985962?skuId=8985962 |
| Carkio 8mm (5/16") M8 Stud Premium Remote Battery Power Junction Post Connector Terminal Kit 2pcs | 1 |
| https://www.amazon.ca/gp/product/B08J7TGPK5/ref=ppx_yo_dt_b_asin_title_o08_s00?ie=UTF8&th=1 |
| 5/16" Nuts & Bolts | |||
| 10 AWG Wire (red and black) |
Modules
These modules were built specifically to handle up to 100a (1c) charge and discharge continuous. Standard lithium ion capacity tests are done at 0.2c which would be 20a continuous. The cells can handle up to 3c but the nickel and wiring was sized to handle 1c loads which is realistically where you want to be.
| NOMINAL VOLTAGE | 3.2V |
|---|---|
| CAPACITY | 100ah (105ah+ is being reported by customers) |
| WATT HOURS | 320 |
| FULLY CHARGED VOLTAGE | 3.65V |
| FULLY DISCHARGED VOLTAGE | 2.5V |
| MAX CONTINUOUS CHARGE | 100A (1C) |
| MAX CONTINUOUS DISCHARGE | 100A (1C) |
| MAX PULSE DISCHARGE (10 SECONDS) | 200A (2C) |
| MODULE WEIGHT | 6.5 lbs |
| MODULE DIMENSION | 7" X 5.5" X 3" |
BMS
LiFePO4 4S 100a BMS W/ LOW TEMP CUTOFF
Connections
Specifications
| Manufacturer | Xiaoxiang |
|---|---|
| Model | SP04S020A |
| Configuration | 4S 100A |
| Chemistry | Lifepo4 3.2V |
| Configuration | Common port with balance |
| Part Number | 16270007 |
Settings
| Overcharge Voltage per Cell | 3.65 |
|---|---|
| Over Discharge Voltage per Cell | 2.5 |
| Discharge Continuous Amps | 100A |
| 10 second Discharge Burst | 200A |
| Charge Continuous Amps | 60A |
| Balancing Current | 60mA |
| Low temp cutoff | 32° F (0° C) |
| High temp cutoff | 167° F (75° C) |
Bluetooth Module
The Bluetooth module is an optional accessory that may be used to configure and monitor the BMS.
To use, simply plug the 4-pin connector into the BMS. The BMS must be connected to the battery, with the balance lead connected in order for the Bluetooth module to operate.
Note that other Bluetooth modules are not compatible.
For best reception, mount the module high, ideally away from metal. Do not mount it inside of a metal enclosure. The Bluetooth module may be left connected to the BMS for long periods of time. It will go into a deep sleep mode when not in use.
Software
XiaoXang BMS
https://apps.apple.com/us/app/xiaoxiang-bms/id1375405426
Big Battery
XiaoXiang Electric
Build Pictures
