80v5ah 4c lifepo4 7lb hack battery

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electricridefl
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Joined: Friday, November 24, 2006 - 20:03
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80v5ah 4c lifepo4 7lb hack battery

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The white battery is 36v10ah, is plugged in series with an identical one I I don't have to charge at work now. I ride 5 miles and then park, and then ride home, has same brisk power at end. Perhaps range would be 15-20 miles at stop and go 20-30mph urban blast. My 72v 10ah battery was 89v this morning...I have to tie down stuff in my basket better. I got some great exercise this morning...no gas to buy...

This battery is perfect for ebike, this one rated for clyte brushless 409 rear motor, so I can 2hp , and close to 35mph, whisper quiet,
This battery would be perfect for go hub or wilderness energy 36v hubmotor...I can't help but wonder of my bike with a 406 or so with a simple 36v battery , because this 72v eats up power,

the silver battery is I cut the parallel 5ah cells and reassembled the whole thing as 24 single cells in series...thin little foil pouches flat with little foil power tabs, no bms, on first charge after short bike ride at 20a draw, no problem, then charge on 36v sla charger ( 2 36v halves of battery from series to parallel ) and all cells are equal at 3.4 volts, and then float turns on, but not sure how much charge battery gets, resting voltage at 40.5 or so. The foil pouches are stamped 4950mah 3.2v. no heat or smells observed. I could put bms , but will put this battery to 20a ebike test.

I will make mount like the white battery that clips to rear frame post and then pivots into center of frame, fits snugly, then battery can't come off, can only be pushed horizontally, so cable tie holds the taped in aluminum thin bar around frame tube in the front...the battery goes on or off easily and is secured well,

I would be careful about putting a 48v ping battery for 36v cylte controller with 55v mofsets, because his 48v battery will surely eclipse 55v after full charge..

electricridefl
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Last seen: 12 years 7 months ago
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Re: 80v5ah 4c lifepo4 7lb hack battery

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Here is pick of bike with my 80v5ah lifepo4 7lb battery, no bms.
the bike weigh 100lbs before with 9ah sla battery.
With this battery weighs 70lbs. I rode around some more with this batt tonight. The bike feels like a bicycle now lightweight. But wheelies so easy now . And goes very fast. I've been commuting with my 10ah 80v battery. No need to charge at work. Then charge at home 2 36v batteries with one charger...I leave on overnight, and charges up perfectly everytime...no problem with these batteries or bms...I'm not in any hurry to charge the non-bms battery. I did charge once after light use. I charged it with 36v sla charger (charged 2-36v 5ah in parallel). All the cells measured exactly the same while charging @ 3.42v ea, then sla charger switched to float. I want to discharge the battery deeper before next charge. And then maybe try a higher voltage charger. I have no way to tell how much capacity is left...I did get the resting voltage below 40v (for 12 cells). Can anyone tell me if I can tell by resting voltage when I am about to run out of charge? Once I ran a good discharge on my 10ah set, they charge up to 44.6v each now. I suppose something will be damaged if I discharge these cells to far? ...Just wondering if someone has checked voltage when bms for ping battery shuts off...This battery is the way to go...That little 80v 5ah battery is amazing...

Aerowhatt
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Joined: Wednesday, January 9, 2008 - 18:38
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Re: 80v5ah 4c lifepo4 7lb hack battery

I discharged a ping battery 12 cells "36volt 20ah" and took 19.57ah out of it recording data from the discharge. The end voltage while still under a 10.1 amp load was 32.5V (this was not ended by the BMS). The resting voltage after ten minutes or so was 36.9 V. What I've read about this chemistry is to not go below 2.7 volts per cell under load.

The Ping BMS let's it go lower under load before disconnecting. It happens pretty fast so it was hard to get an accurate number. Looks like about 2.2 volts though. But then again the BMS disconnects well before the load you are asking of your BMS free battery. Mine disconnected at about 32amps when first tested. I would say the resting voltage of 36.9 should be your lowest target. The battery was pretty empty at that voltage. It was still producing power at 1/2C amp rate but one cell was begining to have a temperature rise relative to the others which is a sign that it's all but empty.

At 4C without a BMS I wouldn't expect this battery to last that long. Taking the voltage too high or too low does damage in a hurry. Best not to try to fully charge, or discharge it and just use the wide middle range as long as it will hold up.

Aerowhatt

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