This article details a year-long review and capacity test of a DIY 12V 48Ah LiFePO4 battery. Built using a simple 2P 4S configuration with eight readily available LiFePO4 cells and a basic, yet functional, BMS, this project prioritized cost-effectiveness without sacrificing reliability. The battery served as the primary power source for an off-grid cabin for a full year, enduring varying temperature conditions and numerous charge-discharge cycles.This hands-on project demonstrates the feasibility and surprising durability of building a high-capacity LiFePO4 battery on a budget. The subsequent capacity test, comparing initial performance to that after a year of continuous use, reveals the battery's impressive long-term capacity retention. The results highlight the viability of this DIY approach for powering various 12V systems, from sheds and cabins to camper trailers, and underscore the potential cost savings and customization options available to DIY enthusiasts.
Pros And Cons
- Relatively cheap to build
- Simple to build if you understand the basics
- Didn't hit the rated capacity
- Uses a Dolly BMS 100 which may be overkill and lacks a temperature sensor
Read more: OUKITEL P2001 PLUS Review: Best Budget Portable Power Station?
The Build: A Simple 2P 4S Configuration
I constructed a 12V 48Ah DIY lithium iron phosphate battery over a year ago using a 2P 4S configuration. This involved using eight individual LiFePO4 cells arranged in two parallel sets of four cells in series. The simplicity of this design makes it highly accessible for DIY enthusiasts.
The battery incorporated a somewhat basic BMS (Battery Management System), not the smartest option, yet functional. This seemingly simple build proved surprisingly reliable and served as the primary power source for my off-grid cabin for an extensive period.
The choice of components was driven primarily by cost-effectiveness. While the cells didn't quite hit their rated capacity, their affordability made the project viable. The selection of a slightly overpowered BMS added to the robustness of the system.
Long-Term Performance and Capacity Test
After a year of continuous use in various temperature conditions (hot and cold), and numerous charge-discharge cycles, the battery underwent a thorough capacity test. The initial capacity test immediately after the build served as a baseline for comparison.
The test involved discharging the fully charged battery at a controlled rate. The results were closely monitored to determine the remaining capacity after the extensive period of operation. The long-term performance was a crucial aspect of this evaluation.
The final result showed a surprisingly high capacity retention. After over four hours of discharge, the battery delivered a significant amount of energy.
Final Thoughts and Future Applications
The capacity test results proved the long-term durability of the DIY LiFePO4 battery, exceeding expectations given its simple design and budget-friendly components. While the chosen components weren't top-of-the-line, they provided reliable performance for the intended application.
I've found numerous applications for this type of battery, including powering small 12V systems in various projects. My current projects involve powering a shed, a cabin, and a camper trailer.
The project highlights the accessibility of building your own LiFePO4 battery, even on a budget. The potential for cost savings and customization make DIY batteries an attractive option for various applications.