Can a variable DC power supply charge Thundersky LIFEPO4 battery packs on an electric scooter?
We made some observations on a large electric scooter with 16 cells of Thundersky 40AH in 3 packs with a BMS.
All the voltages mentioned will be the average cell reading, i.e. Total Voltage divided by the 16 cells mentioned.
3.333 V - Scooter is at rest 48 hours or more after a full charge
3.22 V - Scooter voltage, stopped, after running 1/2 of its normal 50 KM range
3.17 V - Scooter voltage, stopped, after showing some minor performance slowdown and voltage sags on the "energy meter" (fuel guage)
3.1 V - Scooter really slow (only walking speed) perhaps due to BMS or controller limiting features to prevent damage to Thundersky batteries.
When using a digital variable DC power supply (0 to 72V, 0-1.5A) to charge a 75% discharged scooter, the Thundersky LIFEPO4 cells:
.. rises to 3.33V in an hour (as shown on the power supply display), obviously not charged much.
.. rises slowly to 3.7V, but voltage rise imho is rising faster than my own estimation for a correct State of Charge.
What is your own experience with using a variable power supply on LIFEPO4 prismatic cells, like Thundersky batteries?