CrossRoads
Active member
- Local time
- 12:44 AM
- Joined
- Apr 28, 2022
- Messages
- 114
My longstanding holy-grail quest to find an affordable but decent quality third-party aftermarket e-bike battery takes yet another anti-climactic turn.
I picked up a 72V 30 amp-hour BtrPower Li-Fe-PO4 battery pack with a 50 amp BMS and took it for a test ride in my electric cargo bike with a Grin high-voltage Frankenrunner and a 9-Continents RH212 . I don't mind the mildly extra weight of the Iron-phosphate, since my cargo bike already weighs upwards of 150 lbs.
My long-jon cargo bike is a power-hog and needs every bit of the watts the hub can deliver just to saunter down the road at a decent clip. Power delivery was great, 1600 watts, for the first few miles, then it just started scaling back power delivery down to 800 watts after 3 or 4 miles. Because the grin cycle-analyst system tells me real time data about everything including what the permanent magnets had for breakfast that morning, i know the powering down was NOT due to heat roll-back. So, I guess there's a mosfet in the battery that is scaling the power down due to over-current or something? 1600 watts is only 22 amps, well under the 50 amp BMS rating. That doesn't make sense.
I understand you get what you pay for, but i simply refuse to believe that in order to get a battery which performs to specification you have to spend two arms and a leg. Bicycle motor-works wants $800 for a 16 amp-hour battery, or $1600 to get 32 amp hours, that's two and a quarter TIMES the price per amp-hour, and nearly the cost of a brand new ebike. BtrPower was the last on my list of potential quality but affordable battery options that I was hoping could be the ticket.
I guess i'm just writing to see if anyone has experience with BtrPower, and also this is my first Iron-phosphate battery, so maybe this is just a typical feature of Iron Phosphate?
To date then, the best option remains to be: buy an ill-reputed Unit Pack Power Li-NMC battery, and 2 out of 3 that they produce will perform as specified. The 1 out of 3 where the BMS is junk, replace the BMS.
I picked up a 72V 30 amp-hour BtrPower Li-Fe-PO4 battery pack with a 50 amp BMS and took it for a test ride in my electric cargo bike with a Grin high-voltage Frankenrunner and a 9-Continents RH212 . I don't mind the mildly extra weight of the Iron-phosphate, since my cargo bike already weighs upwards of 150 lbs.
My long-jon cargo bike is a power-hog and needs every bit of the watts the hub can deliver just to saunter down the road at a decent clip. Power delivery was great, 1600 watts, for the first few miles, then it just started scaling back power delivery down to 800 watts after 3 or 4 miles. Because the grin cycle-analyst system tells me real time data about everything including what the permanent magnets had for breakfast that morning, i know the powering down was NOT due to heat roll-back. So, I guess there's a mosfet in the battery that is scaling the power down due to over-current or something? 1600 watts is only 22 amps, well under the 50 amp BMS rating. That doesn't make sense.
I understand you get what you pay for, but i simply refuse to believe that in order to get a battery which performs to specification you have to spend two arms and a leg. Bicycle motor-works wants $800 for a 16 amp-hour battery, or $1600 to get 32 amp hours, that's two and a quarter TIMES the price per amp-hour, and nearly the cost of a brand new ebike. BtrPower was the last on my list of potential quality but affordable battery options that I was hoping could be the ticket.
I guess i'm just writing to see if anyone has experience with BtrPower, and also this is my first Iron-phosphate battery, so maybe this is just a typical feature of Iron Phosphate?
To date then, the best option remains to be: buy an ill-reputed Unit Pack Power Li-NMC battery, and 2 out of 3 that they produce will perform as specified. The 1 out of 3 where the BMS is junk, replace the BMS.
