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Old 04-26-2016, 11:21 AM   #3 (permalink)
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Join Date: Sep 2012
Location: Victoria, BC
Posts: 1,271

Firefly EV - '98 Pontiac Firefly EV
90 day: 107.65 mpg (US)

Little Boy Blue - '05 Toyota Echo
90 day: 33.35 mpg (US)

BlueZ - '19 Nissan 370Z Sport
90 day: 17.19 mpg (US)
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Laste year, I picked up a bunch of B-grade A123 20ah LiFePO4 cells off of ebay, and painstakingly built a "48v" battery...

After some issues with my own ignorance and then issues with the BMS I had, I had to replaced cells as often as I used it. I've got it under control now, but I no longer have enough cells to make a second such battery.

This was how it looked:

I added further protection, in the form of low-voltage alarms made for RC batteries:

This is how it looks now:

It's trouble free at the moment, and it makes audible noise if any cell drop below 3V, so if I accidentally leave my ebike turned on again for some reason, I have a chance of preventing damage...

Specs: 20ah @ ~52V. BMS supposed limit: 100a peak, 50a continuous. I can get 30-40 km on a charge on my current e-bike, running at full speed, with a small passenger.
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