Brian Howell's (of ElectroRide LLC) converted his Myers Motors NMG Sparrow to Li-ion.
The conversion uses:
- 32 each, 130 Ah CALB cells, part number SE130AHA
- (available from stock from CALIB, the US branch of CALB)
- 32 x $ 195 = $ 6240
- Cell inter-connecting straps
- A BMS-X from Thunderstruck Motors
- 32 x $ 15 + $ 150 = $ 630
- Total for electrical parts: $ 6930
- Factor in that you'll have to replace a few cells over time, because the BMS doesn't protect the pack
Brian sells those parts as well, for one-stop shopping convenience.
The traction pack specs are:
The BMS is an analog monitor:
- It does know there's a problem somewhere, but not what or where (which is fine); so it can't display in the cabin which cell is low while you're accelerating
- It doesn't directly protect the pack. Instead, it relies it relies on the user to notice there's an issue, in the hope that the user will do something about it, else the pack is toast (which is not so fine)
- It doesn't measure current, and therefore:
- It doesn't protect from over current
- It calculate SOC (which is fine, because the Sparrow has a Link 10 battery monitor)
- It doesn't measure temperature (which may be OK)
Instead of using the maximum available space, Brian chose to go for a better organized, less crowded approach.
The installation is very clean looking.
Cells are installed in 3 places:
- Under the hood
- Under the seat
- Under the hatch
Under-hood battery, in progress
Under-hood battery, complete