Turnigy LiFEPO4 packs - Page 6 - RC-Monster Forums

lutach · 11.20.2009, 04:16 PM

Another player in the Life cells, but lets see if the S boys will go MA style on prices: http://www.redrc.net/2009/11/speed-p...of-life-packs/. They offer the choices I mentioned before. Looks like MA is lacking behind and have they gone a bit quiet? I'll be posting this at similar threads in here, so in advanced.....SORRY FOR SPAMMING.

snellemin · 11.20.2009, 05:08 PM

SPAMMER! The S boys are most likely gonna match MA in price. I'll chill with my old school A123's untill the dust settles.

lutach · 11.20.2009, 05:33 PM

Quote:

Originally Posted by snellemin

SPAMMER! The S boys are most likely gonna match MA in price. I'll chill with my old school A123's untill the dust settles.

Where's that spammer....He should be banned

.

lincpimp · 11.20.2009, 07:18 PM

Ok, so I got my turnigy 2s2p pack in today. Looks good, but i will give it a test in something, maybe a novak gtb with a 3.5 in a 10th 2wd buggy? That should put a load on it, geared for 60 or so...

sikeston34m · 11.20.2009, 07:30 PM

Quote:

Originally Posted by lincpimp

Ok, so I got my turnigy 2s2p pack in today. Looks good, but i will give it a test in something, maybe a novak gtb with a 3.5 in a 10th 2wd buggy? That should put a load on it, geared for 60 or so...

That's a good test bed for it.

I think you'll see, they don't mind a big amp load at all.

My 2S2P packs went through some more testing today.

This time in an E maxx using a Novak HV Motor powered by a MM Pro.

The MM Pro is smooooooooth in sensored mode.

What I did different with testing was:

Using an AUTOMOTIVE type charger, which yields a 14.5 volt charge cutoff, I recharged the packs in series, at 20 amps!

The entire recharge took less than 20 minutes! I did monitor cell voltage with a meter while recharging.

They didn't mind this treatment at all. The packs were cold when the charge cycle started, and cold when it was done.

I was tempted to kick the charger up to 40 amps. Hmmm.......should I try it?

40 amps would be about a 9C charge rate.

11.20.2009, 11:06 PM

go for it

sikeston34m · 11.22.2009, 07:26 PM

Quote:

Originally Posted by Brushless Moose

go for it

I just took the E maxx out for another run a few minutes ago.

Didn't bother charging it up, since it was still partially charged from the last time.

About 10 or 12 minutes of running had it on the LVC.

I then hooked it up to the Automotive Charger again, only this time, I couldn't resist.

Bumped it up to 40 amp charge rate!

Then watching the voltage of each cell to make sure everything was going right, I noticed my home-made 16 Ga wire lead off the charger was getting pretty warm. LOL

I believe the small Ga. charger lead was why it was "only" charging at 36 amps.

The packs didn't seem to mind this at all! I can't believe it really.

From fully Dead, to fully charged took less than 10 minutes. Again, I didn't detect any heat being added from the high charge rate. Then out for another run. Same Power, Same Punch.

36 amps is 8C. They can handle it!

IF any of you guys try this, remember, the Automotive charger ONLY works if you charge 4S in series.

I checked the balance of each pack. The cells are still within .003 volts of each other.

They haven't been balanced since New, only checked.

Not bad for "reject" cells huh?

lutach · 11.22.2009, 08:49 PM

Not bad at all for rejects. Have anyone tried it with the grade A cells from you know who?

fastbaja5b · 11.22.2009, 08:54 PM

Quote:

Originally Posted by lutach

Not bad at all for rejects. Have anyone tried it with the grade A cells from you know who?

I'd offer to try, but I would need to take out a second mortgage on the house to buy the packs!

suicideneil · 11.22.2009, 10:13 PM

Make sure someone shoves all this info under Jason's nose on whatever forum hes lurking on, love to see what his responce will be, if any. When he refuses to issue his own graphes and charge/discharge data, it'll be plain as day that MA are all mouth & no trousers...

lutach · 11.22.2009, 10:35 PM

Quote:

Originally Posted by suicideneil

Make sure someone shoves all this info under Jason's nose on whatever forum hes lurking on, love to see what his responce will be, if any. When he refuses to issue his own graphes and charge/discharge data, it'll be plain as day that MA are all mouth & no trousers...

MA could've done something like this: http://www.rcgroups.com/forums/showthread.php?t=1078049, but I think the MA boys don't know how to hack the graphs to make them look good

and that's the reason they don't post anything. Here's a thread with good results so far: http://www.rcgroups.com/forums/showt...1143540&page=2.

sikeston34m post your info there and call out the MA guys to see what they can say about the reject cells

.

sikeston34m · 11.22.2009, 10:57 PM

Quote:

Originally Posted by lutach

MA could've done something like this: http://www.rcgroups.com/forums/showthread.php?t=1078049, but I think the MA boys don't know how to hack the graphs to make them look good

and that's the reason they don't post anything. Here's a thread with good results so far: http://www.rcgroups.com/forums/showt...1143540&page=2.

sikeston34m post your info there and call out the MA guys to see what they can say about the reject cells

.

Those guys are watching this thread. That's why they accused you and BN of playing games between there and "another" forum.

It's because they are watching this thread and the "60C really?" thread.

They are alot of "Talk". The proof is in the pudding.

That's why we should put these packs up against their "Green" packs on legit discharge equipment. Or at least an Eagletree running the same setup.

I really enjoyed seeing the discharge graphs in the link you posted Lutach.

I do believe these are holding voltage above 3.0 - 3.1 volts per cell right up to the very end. The discharge curve is VERY flat and at the end they drop suddenly.

I'm tempted to setup my E Revo with these also, then buy another Automotive charger.

Picture two Monster Trucks geared for 40mph, being charged in less than 10 minutes, only to do another 30 minute run.

It's a play all day kinda setup.

lincpimp · 11.22.2009, 11:45 PM

Interesting, I have a really nice automotive charger at the shop, all digital. It has a 6v setting too... Maybe I should try the 2s pack on that? HeHe, it can do 60 amps... What does that work out to, 13+c....

Maybe stick to the 20 amp setting, that should still do the job in 15 mins. I am sure some of the plane guys will try a 3s pack with the "zip charging" method. That is basically a 12v power supply (A big one that can be set) and a certain length of certain gauge wire to limit the current. One guy was charging the 2300 cells in 3 or 4 mins....And had hundreds of cycles as well.

sikeston34m · 11.23.2009, 12:05 AM

Quote:

Originally Posted by lincpimp

Interesting, I have a really nice automotive charger at the shop, all digital. It has a 6v setting too... Maybe I should try the 2s pack on that? HeHe, it can do 60 amps... What does that work out to, 13+c....

Maybe stick to the 20 amp setting, that should still do the job in 15 mins. I am sure some of the plane guys will try a 3s pack with the "zip charging" method. That is basically a 12v power supply (A big one that can be set) and a certain length of certain gauge wire to limit the current. One guy was charging the 2300 cells in 3 or 4 mins....And had hundreds of cycles as well.

The 6 volt setting should work fine for 2S.

Recommended charge cutoff is 3.6 volts per cell.

I opened up my "Black and Decker

" automotive charger and soldered a "little" 16 Ga. lead directly to the outputs on the board.

The cells topped off right at 3.55 volts per cell. Slight Calibration error, or added resistence in the lead? Not sure, but it works perfectly.

My advice is, make sure your charger terminates charge on the 6 volt setting at 7.2 volts or less and you're good to go.

Wait a second! I'm sure if you "surf" the net, you could find a "GREEN" Lifepo4 charger for $567,789,234 Gazillion dollars!

It's the BEST too! Much better than all those other "reject" chargers!

11.23.2009, 02:28 PM

I am glad to see you guys talking about these, I have been wanting a set of LiFe for my E-Maxx that does not have lipo cut off. I had wondered about these, they seemed almost to good to be true, considering the amount a certain website that advertises a lot wants for theirs......