Buggies Gone Wild Golf Cart Forum - View Single Post

Volt_Ampere · 07-17-2021, 08:49 AM

I have two carts running NMC (Leaf modules). I prefer this chemistry for my use - your results may vary. Another "feature" of NMC is that you can pretty accurately predict SOC from the terminal voltage. My cart has a SOC readout that is probably good to 5%. I used the published discharge curve for my cells to program a table lookup SOC that I use to determine when to charge. I also have an odometer on my cart and I know from experience that I can play three rounds of golf including driving to and from the course and still have 25% SOC.
I have used LiFeP04 cells in other applications and it is near impossible to measure SOC based on cell voltage. To measure SOC with these cells, you need to use a much more complex method like "coulomb counting". Doing the accurately in a golf cart with the pulsed current loads requires tricky circuit design.

07-17-2021, 08:49 AM	#4
Volt_Ampere Gone Wild Join Date: May 2012 Location: Rio Verde, Az Posts: 7,193	Re: LiFePO4 vs. NMC Chemistry I have two carts running NMC (Leaf modules). I prefer this chemistry for my use - your results may vary. Another "feature" of NMC is that you can pretty accurately predict SOC from the terminal voltage. My cart has a SOC readout that is probably good to 5%. I used the published discharge curve for my cells to program a table lookup SOC that I use to determine when to charge. I also have an odometer on my cart and I know from experience that I can play three rounds of golf including driving to and from the course and still have 25% SOC. I have used LiFeP04 cells in other applications and it is near impossible to measure SOC based on cell voltage. To measure SOC with these cells, you need to use a much more complex method like "coulomb counting". Doing the accurately in a golf cart with the pulsed current loads requires tricky circuit design.