imorton
1 kW
Hi Guys & Girls, I have a scooter and had SLA's and when it was time to change them, I bought a 48v 15Ah LifePo4 16s battery from Sun Thing @ 2 years ago. I tested it at the beginning and it produced @ 14.5 Ah and seems to balance fairly quickly. My average trips are @ 6-10 kms, and have done a few 40km trips. I also do @ 100 trips a summer to back & forth to work that is only 2 kms (1km each way) and I end up charging the battery at the shop. I have done @ 2000 kms with the scooter with the 48v 15Ah LifePo4.
I just wanted to ask a few questions...
1) It came with a bulky 5amp charger (it also charges to 59.9v), but I tend to always use my spare 3amp 48v charger that appears to charge up to 59.9v and stays there while it balances the pack. Is the 59.9v a little high, and is it damaging the cells?
2) When I take the battery off the charger, the voltage drops to 55 or 56v, and if I ride the scooter a little, it will stabilize at 53.24v (I presume this is good since 3.3v x16 = 53.28v)...?
3) I am curious what is a normal voltage drop as when I ride and draw .5C (7-8amps) the voltmeter says @ 51v, and when I draw @ 1C (15-16 amps) the voltage drops to 49v. If I hammer the throttle and draw 25amps, the voltage drops to @ 47v. I presume that these are normal/healthy numbers for a 15Ah LifePo4 battery?
4) I am a big guy (250lbs) and ride at @ 22km/h (appears to be a quiet/efficient speed) and have figured out that the scooter consumes .4Ah per km, or 20Whr/km. If I did @ 2000 kms on the scooter, at 20Whrs/km, I assume I consumed 40k watt hours. So if my calculations are correct, I have only used @ 55 cycles from it, and the battery should do @ 1000 cycles...?
5) So it appears that I will never wear out the battery from exceeding it's cycle life specs, but how long does a LifePo4 used this way last.... 3,5,7,9 years?
You guys are simply amazing with all your knowledge, so thanks in advance for any replies and info that you can share.
IAN
I just wanted to ask a few questions...
1) It came with a bulky 5amp charger (it also charges to 59.9v), but I tend to always use my spare 3amp 48v charger that appears to charge up to 59.9v and stays there while it balances the pack. Is the 59.9v a little high, and is it damaging the cells?
2) When I take the battery off the charger, the voltage drops to 55 or 56v, and if I ride the scooter a little, it will stabilize at 53.24v (I presume this is good since 3.3v x16 = 53.28v)...?
3) I am curious what is a normal voltage drop as when I ride and draw .5C (7-8amps) the voltmeter says @ 51v, and when I draw @ 1C (15-16 amps) the voltage drops to 49v. If I hammer the throttle and draw 25amps, the voltage drops to @ 47v. I presume that these are normal/healthy numbers for a 15Ah LifePo4 battery?
4) I am a big guy (250lbs) and ride at @ 22km/h (appears to be a quiet/efficient speed) and have figured out that the scooter consumes .4Ah per km, or 20Whr/km. If I did @ 2000 kms on the scooter, at 20Whrs/km, I assume I consumed 40k watt hours. So if my calculations are correct, I have only used @ 55 cycles from it, and the battery should do @ 1000 cycles...?
5) So it appears that I will never wear out the battery from exceeding it's cycle life specs, but how long does a LifePo4 used this way last.... 3,5,7,9 years?
You guys are simply amazing with all your knowledge, so thanks in advance for any replies and info that you can share.
IAN