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https://apps.apple.com/th/app/xiaoxiangelectric/id1576622653
Build
Battery Case
| Measurement | Width/Length/Height |
|---|---|
| Battery Cell | 7.5" X 3" x 5.5" |
| Battery Cells x 4 | 7.5" X 12" x 5.5" |
| Selected Box(Exterior) | 7.7" x 15.4" x 10.2" |
| Selected Box(Interior) | 7" x ? |
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We couldn't find a box with the ideal interior dimension of 7.5" x 12", so we went with this bigger ammo box and placed the cells on their sides.
Cell Top Balancing
In order to ensure we get the max capacity out of our new battery, we need to top balance the cells.
See https://www.youtube.com/watch?v=x5ABvbbics8
Charge the battery in it's 4S configuration and then disassemble.
Connect all cells together in parallel and charge at 3.65v until very little current is flowing into the batteries.
Build Pictures
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Battery 1 - 112 Ah
Battery 2 - 95Ah - Before Top Balancing
Battery 2 - 118Ah - After Top Balancing
Cost Breakdown
I ordered enough to build 3 batteries in order to save on shipping.
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| Item | Cost | Currency | Exchange | CA$ |
|---|---|---|---|---|
| Ammo Box ($16.99 + HST) | $19.19 | CA | - | $19.19 |
| 5x 5/16" Ring Terminal | ||||
| 10 AWG Red Wire | ||||
| 10 AWG Black Wire | ||||
| Solder | - | |||
| Strap | $3.00 | |||
| Heat Shrink Tubing | ||||
| 5/16 Nuts and Bolts | ||||
| Zip Ties | ||||
| Duct Tape | ||||
| Total |
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| Reference | URL |
|---|---|
| Smart BMS | https://batteryhookup.com/products/12v-lifepo4-smart-bms-w-low-temp-cutoff |
| 3.2V 100ah MODULES | https://web.archive.org/web/20210516124542/https://batteryhookup.com/products/new-battery-hookup-lifep04-32650-3-2v-5000mah-cells-1 |
| BMS Manual | |
| Xiaoxiang BMS Manual | https://github.com/smagicld/xiaoxiangBMS |
| Software | https://www.lithiumbatterypcb.com/smart-bms-software-download/ |
| OverkillSolar BMS Files | https://github.com/FurTrader/OverkillSolarBMS |
| Arduino Library | https://github.com/FurTrader/OverkillSolarBMS/tree/master/Arduino |
| Communication Protocol | |
Communication Protocol | |
Build Video $420 100AH LiFePO4 Build - BatteryHookup.com Modules - Super Easy Assembly! COMPLETE DIY GUIDE! | https://www.youtube.com/watch?v=uN1h0XIpfTg&t=1401s |
| DIY 100AH LIFEPO4 BATTERY PARTS LIST | https://jasonoid.com/diy100ahlifepo4/ |
| How to Top Balance LiFePO4 Battery Cells Quickly (and when you need to do it) | https://www.youtube.com/watch?v=x5ABvbbics8 |