Posts by david85
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Correct, although I carried out testing on a 12.8V sample first to try and verify the reserve capacity and High current draw (although I was only able to do a rough test of 3C @ 10 seconds). So far the battery has performed well, but with only about 2000 kilometers on all electric, it doesn't say much.
The company that sold my batteries was an interesting one because they carried every kind you could imagine. LiFePO4 was the most obvious but they also had NiCad, NiMH, and NiFE among a long list of others among in and lithium varieties.
What gives me some reason to celebrate is that Kevin's battery is a carbon copy of mine in terms of rated capacity AND system voltage.
The company that sold my batteries was an interesting one because they carried every kind you could imagine. LiFePO4 was the most obvious but they also had NiCad, NiMH, and NiFE among a long list of others among in and lithium varieties.
What gives me some reason to celebrate is that Kevin's battery is a carbon copy of mine in terms of rated capacity AND system voltage.
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What I did wasn't completely without precedent at the time. Back then I had already looked at conversions using thundersky LiFePO4 cells that had a few years on them and I took the time to contact some directly to ask how they were performing. No one that I found had anything bad to say about them.
TS is of course a different company, but the chemistry is the same and after I received a sample that worked as they claimed, I felt "less uncomfortable" about buying something like this. They also answered all my questions and when I plotted my measured discharge curve to compare it to their plot it was a perfect match. I sensed there was also a realization on behalf of many chinese companies that they had to overcome much of the bad wrap that TS placed on all of them a few years ago when a large group buy of lithium batteries turned sour and they didn't perform as advertised. This was before TS introduced the current gold standard LiFePO4 series.
The chinese are slowly starting to embrace western 3rd party payment methods like credit cards and paypal or equivalent so a direct wire transfer is becoming obsolete (thankfully). Are they better than thundersky or sky energy? I have no idea. There simply aren't enough miles on my car to say for sure.
TS is of course a different company, but the chemistry is the same and after I received a sample that worked as they claimed, I felt "less uncomfortable" about buying something like this. They also answered all my questions and when I plotted my measured discharge curve to compare it to their plot it was a perfect match. I sensed there was also a realization on behalf of many chinese companies that they had to overcome much of the bad wrap that TS placed on all of them a few years ago when a large group buy of lithium batteries turned sour and they didn't perform as advertised. This was before TS introduced the current gold standard LiFePO4 series.
The chinese are slowly starting to embrace western 3rd party payment methods like credit cards and paypal or equivalent so a direct wire transfer is becoming obsolete (thankfully). Are they better than thundersky or sky energy? I have no idea. There simply aren't enough miles on my car to say for sure.
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Uh, Pete? What the heck is Yttrium?If you can afford to buy the new Winston Batteries with Yttrium you'd be much better off than with Hi-Power Cells. I got my Hi-Power because I got a good deal. I still like mine because of the price I paid, not because of the quality. They are good but are 08 batteries and not as good as others like TS or Calb. So I will continue to use mine until I can get the new Winston batteries.
Pete
Proof that I've been out of the loop lately.
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Thanks Pete.Yttrium is a reactive metal that was used in the TS battery chemistry to basically contaminate the matrix but what that does is hold the matrix together better so it does not collapse over time near as fast. So what it is there for is structural integrity and increased the cycle life by a considerable amount with out really affecting the performance of the battery. Very little is used but that is all that is needed. Kind of like mixing carbon into iron to make steel. A little goes a long way. So now 70% DOD is up to 5000 cycles. Not quite doubled. Old style at 70% DOD was set at 3000 cycles.
Pete
Sounds promising.
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Did some looking on Alibaba, and ran the numbers on one example. I came up with roughly 150wh/kg on one of them but I don't know if that can be trusted. Do you know if the energy density is any different? Last I heard the "Blue" sky energy LiFePO4 version was top of the food chain with 115 wh/kg with cells like mine being around 90.
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