Electric Bikes - Where do you buy LiFePO4 batteries? (Non-Ping) looking for Higher C and good quality.

I read that Ping batteries are good, but I also read they have had some problems.

They also have a poor "C" rate.

Any idea where a good place is to buy the Thundersky's, or Headways, or some high-quality equivalent LiFePO4? Or is Ping the only decent and reliable source of getting LiFePO4 at 2C

Ping has a good site for sales, and apparently good customer service, just slow turn around time for repairs. Are there others in the 5C realm that are as good as Ping?

Wallet and battery case do not allow for a 48V 40Ah Ping battery unfortunately.

http://www.coronn.com/poormansecologicalvehicle/wp-content/uploads/2009/07/lifepo4battery.jpg
http://www.e-mtb.com.au/images/38120S-2.jpg

I read that Ping batteries are good, but I also read they have had some problems.

They also have a poor "C" rate.

Any idea where a good place is to buy the Thundersky's, or Headways, or some high-quality equivalent LiFePO4? Or is Ping the only decent and reliable source of getting LiFePO4 at 2C

Ping has a good site for sales, and apparently good customer service, just slow turn around time for repairs. Are there others in the 5C realm that are as good as Ping?

Wallet and battery case do not allow for a 48V 40Ah Ping battery unfortunately.

http://www.coronn.com/poormansecologicalvehicle/wp-content/uploads/2009/07/lifepo4battery.jpg
http://www.e-mtb.com.au/images/38120S-2.jpg

I built my 24V 20AH LIFEPO4 pack using Thundersky cells that I bought from Arizona-based US distributor Elite Power Solutions. (I don't use a BMS but rather a CellLog 8 to monitor discharge and recharging, if you have e-brakes, the CellLog can perform LVC like a BMS.) I bought my cells when they were on sale for $104 per 4-cell unit, for a total of $208 plus $15 in shipping (I'm in the western US, shipping to the east coast would be a bit higher). The regular price is a reasonable $120 for a 4-cell unit. I' extremely happy with my Thundersky battery and will be ordering 8 more cells next month and building a second pack. Here's a photo of my cells configured into a 24V 20AH pack as well as a photo of the completed battery pack in the Currie rear rack (the CellLog 8 is in the silver box).

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Thundersky can just barely handle 2C. I'm using a 40 amp discharge (2C) on my thundersky and they barely handle it. I somehow damaged one cell but I'm not sure if that was due to quality control problems or something that I did but the rest of my cells are just fine now with 300 miles + on them. The good thing about a Thundersky pack is that if you damage one cell, the rest of the pack is still fine so you can keep going and keep using it very easily. I damaged one cell and it did not damage any others.

You need a 2C dishcarge? If it's like 35 amp then I would go with the Thundersky's but if it's more like 45 amps then I would go with something else. If you need high discharge, why not go with LIPO? I read about someone only using 50 % capacity with his LIPO batteries and was able to use them for 5 years and get longer use out of them. I only use 50 % of my LIFEPO4 batteries.

Also, I read that the Bosch Fat packs were a really good source of lithium but they are pretty expensive. Thundersky is probably the best value for 2C lifepo4 batteries and they are probably the most safe too because they have a vent at the top that prevents fire. (I know all about that... lol. The vent does indeed work. ) The headways have a rust problem I've heard and I read that they aren't really all that much more capable than Thundersky. Plus, they aren't prismatic cells and if one cell goes, you could have big problems because you are likely to use a parallel and series connection whereas with Thundersky, you only use a series connection. So if one headway goes, and it's in parallel with another one, you've just seriously weaked the entire pack's capacity whereas if one thundersky goes, you still have the same capacity as before, just lower voltage.

Thundersky can just barely handle 2C. I'm using a 40 amp discharge (2C) on my thundersky and they barely handle it. I somehow damaged one cell but I'm not sure if that was due to quality control problems or something that I did but the rest of my cells are just fine now with 300 miles + on them. The good thing about a Thundersky pack is that if you damage one cell, the rest of the pack is still fine so you can keep going and keep using it very easily. I damaged one cell and it did not damage any others.

You need a 2C dishcarge? If it's like 35 amp then I would go with the Thundersky's but if it's more like 45 amps then I would go with something else. If you need high discharge, why not go with LIPO? I read about someone only using 50 % capacity with his LIPO batteries and was able to use them for 5 years and get longer use out of them. I only use 50 % of my LIFEPO4 batteries.

Also, I read that the Bosch Fat packs were a really good source of lithium but they are pretty expensive. Thundersky is probably the best value for 2C lifepo4 batteries and they are probably the most safe too because they have a vent at the top that prevents fire. (I know all about that... lol. The vent does indeed work. ) The headways have a rust problem I've heard and I read that they aren't really all that much more capable than Thundersky. Plus, they aren't prismatic cells and if one cell goes, you could have big problems because you are likely to use a parallel and series connection whereas with Thundersky, you only use a series connection. So if one headway goes, and it's in parallel with another one, you've just seriously weaked the entire pack's capacity whereas if one thundersky goes, you still have the same capacity as before, just lower voltage.

Although LIPOLY is more affordable and has high C ratings, it's still the most dangerous Lithium-based chemistry and subject to thermal runaway if over charged or discharged too deeply. (Swelling is a sign that the cells have been too deeply discharged and may begin to burn. This can happen while in use on an e-bike, just read posts in the Endless Sphere forums.) Although somewhat safer than when first released for the RC market, you are still advised to charge in a safety bag and not recharge in a structure that can burn down. I wouldn't recommend LIPOLY for use on an e-bike unless you're an experienced RC user who knows how to properly handle and use LIPOLY batteries.


http://www.youtube.com/watch?v=z3o_2mwRPdw

[QUOTE=nwmtnbkr;11033038]Although LIPOLY is more affordable and has high C ratings, it's still the most dangerous Lithium-based chemistry and subject to thermal runaway if over charged or discharged too deeply. (Swelling is a sign that the cells have been too deeply discharged and may begin to burn. This can happen while in use on an e-bike, just read posts in the Endless Sphere forums.) Although somewhat safer than when first released for the RC market, you are still advised to charge in a safety bag and not recharge in a structure that can burn down. I wouldn't recommend LIPOLY for use on an e-bike unless you're an experienced RC user who knows how to properly handle and use LIPOLY batteries.

I agree I would not recommend lipoly ether and I use them on my helicopter (not that I know what I'm doing with that thing ether though). Stay with lifepo4 and as morph says if you are looking for 35 to maybe 40a TS is a good pack. But beyond that go with 123s. And for gosh sake don't go with a Ping!!