Lmst

#DIY 100Ah is getting smaller and smaller as time progresses. A recent prismatic cell build with #Daly 100A BMS. (Unfinished #DenCo 5.5Ah build on the left for scale.) #LiFePO4 #BatteryBuild

A 5.5 amp-hour DIY LiFePO4 12V build right next to a completed 100 amp-hour 12V prismatic cell build.

Well well well... what have we here? #LiFePO4 #DIY #BatteryBuild

Four LiFePO4 prismatic cells from ExpertPower US for a do-it-yourself battery build.

Back at it. #DIY #LiFePO4 #BatteryBuild #DenCo

A DenCo battery mid-build process, ready to be QC tested.

Trying out a bigger #DenCo.
#DIY #LiFePO4 #BatteryBuild

The underside of a 4S2P LiFePO4 battery build.

A bigger DenCo battery with a 30 amp BMS.

Some #DenCo Battery Management System (BMS) units, in 20-amp and 30-amp models. #DIY #LiFePO4 #BatteryBuild

A photo of some #DenCo Battery Management System (BMS) units, two 20-amp and one 30-amp shown.

Do you even #LiFePO4?
#DenCo #DIY #BatteryBuild

A bunch of spot-welded LiFePO4 cell packs waiting to be built into usable 12 volt batteries.

Something about this Daly 20A 4S #LiFePO4 BMS seems really cool...
#DenCo #DIY #BatteryBuild

Refining the #BatteryBuild process. #DenCo #LiFePO4

Three DenCo batteries with barrel plug charging adapters.

Quality Control sticker that says "QC Passed 365737". Each battery is serialized and goes through a charge/discharge and voltage test, among other tests.

A pack that turned out to be a poor performer. So I peeled off the blue PVC and added a 1.2A active balancer to the mix. Hopefully I can salvage it. #DenCo #LiFePO4 #DIY #BatteryBuild

A 12-volt "6 amp-hour" custom-built battery pack that turned out to deliver 3.7 amp-hours on first test. So I have added a 1.2 amp active balancer to try and salvage the performance of the stronger cells. The wiring is a little messy, but it's all hidden now under blue PVC shrink wrap.

Testing out a @Renogy 12V 700w inverter (known as "the quietest inverter") and #DIY #Headway #BatteryBuild on our entertainment center while my cat supervises.
With this, I estimate some 8 to 10 hours of TV watching during a power outage. #offgrid #LiFePO4 #PowerbyRenogy

A Sharp flat-screen TV and Apple TV being powered by a 12 volt 64 amp-hour home-built Headway lithium iron phosphate battery and 700 watt Renogy 12 volt inverter while my cat watches next to all her cat toys and cat plants. The TV nominally consumes 60 watts, and the Apple TV about 3.5 watts, and I assume around 85% inverter efficiency. So that amounts to an estimated 10 hours of TV time with a fully charged battery.

The 4S 5.5A #LiFePO4 Active Balancer is an amazing invention! First test with only BMS passive balancing netted me 44.43Ah out of a possible 64Ah (used cells). After adding the active balancer it achieved full 64Ah. #DenCo #DIY #BatteryBuild

My "64Ah" Headway 38120 used 32-cell 4S8P battery build with JAG35 PCB bus board and PCB BMS board kits, and an additional 4S Active Balancer. Went from 44.4 amp-hours to 64 amp-hours with the addition of active balancing.

Graph of my first and second test of the used-cell "64Ah" battery with only passive BMS balancing. One of the parallel cell groups with older cells was limiting the entire pack to 44.4 amp-hours.

The results of the latest battery capacity test with Active Balancing installed. 64 amp-hours, as rated for a new cells build, was achieved.

Top balancing some #Headway 38120 cells. #DenCo #LiFePO4 #DIY #BatteryBuild

7 Headway 38120 cells that measured 3.05V to 3.08V, being top balanced by a variable power supply to match the rest of the cells that measure around 3.3V.

Marking #Headway #LiFePO4 38120 initial cell voltages to sort and top balance. Going to make a 48Ah and a 64Ah 12V #DIY batt for personal offgrid portable use. #DenCo #BatteryBuild

An assortment of used Headway 8Ah 38120 LiFePO4 cylindrical cells from BatteryHookup.com. Some cells are 6 years old, others are 2 years old. Trying to match up initial voltages and ages into groups for better balancing of the overall packs. I plan to make 2 packs from these 56 cells: one that has 24 cells (4S6P), and one that has 32 cells (4S8P) for 48Ah and 64Ah, respectively.

New build complete. Now doing a charging test. #DenCo #LiFePO4 #BatteryBuild

A newly built 6 amp-hour (rated) LiFePO4 12-volt battery, charging at 3.27 amps with a new BMS that looks a lot like a Daly BMS clone.

Getting things ready for another test build. #DenCo #LiFePO4 #BatteryBuild 🔋

Four 32700 Lithium Iron Phosphate (LiFePO4) cells in a cell holder arranged for a 4-series pack (4S) at 6 amp-hours, and a new LiFePO4 20 amp Battery Management System (BMS) unit for testing.

I never realized how "cute" the Headway 38120 cells are. They're tiny compared to the 40152S cells I've worked with. #DenCo #LiFePO4 #DIY #BatteryBuild