Does LiFe have lower IR than LiPo? (4500mAh cells)

Will probably run 6S in my Flux.

the 3s packs won't fit in your flux. trust me, i wanted to do the same thing with my flux. the packs are way too thick.

They will fit in the Desertboy XL conversion.:intello:

I have one 3S here and it fits inside the TVPs, but it will be really tight on the width when I fit another one in.

Why the Xl and not the DB-17?? Just curious, been looking at that one....

An update on the Turnigy 2S2P LiFePo4 I am running. Well I am not running with them but my son is. He managed to puff one of the cells during an extreme discharge. I didn't notice that he was still trying to go up a hill and his truck was just crawling along very slowly. At one point the truck wouldn't even move and that is when I noticed what was going on and asked him to stop pegging the throttle. :mdr: But it was too late. I tried to revive the cell but it is completely dead. So I checked the stock status of HC and they are at zero right now. They are still just $25 :yipi: So I'll wait 'till they come back in stock and get a new one. He still has another pair to play with.

He was running with no LVC so now I updated his MMM with a custom cut off of 9.2 V which is 2.3 V per cell. Should I go higher than that?

I didn't want to waste time trying to save the remaining 3 cells of the pack so I wanted to test the chemical stability of the LiFePo with very sophisticated equipment I happen to have. I hit it with a hammer! I punched 4 big holes in it and nothing. Nothing happened. No smoke, no fire, no smell, no heat. Nothing. I just had to find out for myself.

Sometimes brute force is the best science!

I know when I run my 2S LiFe in my TC I have the LVC set to somewhere like 2.0 or 2.2 V/cell (I'll have to check to be sure). I read that letting the cells drain all the way down past 2.0V/cell decreases their life.

I can't say I've put the cells through their paces very much, as they're in a small and reasonably geared TC, but they have been quite impressive for that application.

I have the 4500mah 3s pack and it holds it's voltage pretty well.

http://i189.photobucket.com/albums/z...mmprojacoa.jpg
http://i189.photobucket.com/albums/z...mmprojacob.jpg
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I agree that they do perform very well. I really like them a lot and am anxious to replace the one that puffed. LiFePo4 batteries are tough but as I have experienced this weekend, you gotta watch out not to drain them too much. Ignorance on my part as I thought that they could survive very deep discharges. Categorize this as user error :smile:
One thing that pleased me is even though this battery was discharged to the point of no return, and after some hard impacts with a hammer, nothing happen that could hurt my soon to be 6 year boy. It puts my mind at ease.

My 7 year old has been using A123's ever since he was 4. In his RC's and power wheels. My wife recently start zooming around in a 10s A123 powered scooter.

It's good to hear that you were able use the science of a hammer to find out the new LiFe cells safety. Have you tried charging them as Lipo or anything about 3.6V per cell?

No I only charge them as A123 cells.

Use the 3s pack in my GTP last nite. Voltage drop was higher at peak. Motor was C50 6L Hacker, gearing 51/16.

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An update on the 4 Turnigy lifepo4 I bought for my son's ERBE a few months ago. I reported that one puffed a little more than a month ago and now, a second one puffed yesterday. No apparent reason for this one, his LVC is set at 2.4 volts per cell. It just puffed a cell. So we're down to two lifepo4 now. I don't like those Turnigys as much as I used too now. It's a bit disapointing.

Thats a bummer to hear :( I was planning on getting some. I currently have a bunch of old A123 racing packs I got off Ebay cheap. I love A123 cells. I mostly like that I can charge them the night before I go out bashing and they hold the charge overnight. They charge fast, are safe to charge in my house with my little girl and they run good enough for me. And I got them pretty cheap. I wanted to get two more for my brushless muggy. I may try making my own from the a123 cells on Ebay.

I also had a cell puff a while back but I want to give them another chance. Only problem is that HK has been out of stock for about a month now. Anybody know how often they restock?

The lifepo4 packs seem to need a few "break in" charges, A main has a warning about this on all their Protec Life packs. Once you do the break in, the chance of cells puffing decreases dramatically no matter what you do.

I took my pack apart and all the cells were puffed.