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I got this IP li po battery from a mate that races a short course truck.

He was not happy with it as it lacked punch & asked me to see what I thought. I gave it a run & it was a little soft in punch & top end volts. I noticed one of the cell packs was ballooning really bad so i left it outside in our under cover out door area just to be on the safe side.

Well it's has got worse as the week went on. So much so it has blown the hard case open to expose the foil wrapped cells.

What really blew me away is it has 3 cells per saddle a total of 6 cells for a 7.4 V pack.

I just had to take a pic before a dunk this pack in a bucket of salt water.

This battery has not been miss treated in any sort of way. Hasn't been discharged too low , over charged & always been charged at the correct C rating!!!

Happens.

at what voltage was it stored between uses?

Paul

Been using mine for my DESC410, with 4800kv revtech and running 25mins plus, no issues so far.havr to trim down The my throtle to 80 due to the massive power.

Always store it at required voltage level.mine is running 2 years now.
Cant complain with my IP. Maybe just bad cells or something as what we race in,there are no A/C power amd we normally run down all the batts all the way down till the voltage cutoff kicks in.

I've had a few go "fat" on me over the years, but never to that extreme. Mine admittedly were from being stored at too high of voltage. I'll sometimes charge a pack that I plan on running and then get distracted by a shiny object or a butterfly or something and keep it at full charge for several weeks. Most of them have always still performed fine. I'm about to do a clean sweep and replace all my lipos for the Winter oval season.

I seem to be having bad luck with shorty packs...2 Losi Xcelrion & 1 Revtech...always treated fairly, never run flat and charged @ 1C, all 3 gave up the ghost and puffed up. The 2 Losi packs I salvaged some cells and made little crawler packs for my son, the Revtech I havent touched yet. Its barely rounded, but enough for me to know its time has come.

I have 2 Orion 3600 packs that I bought when they first came out...4 year ago or more? My son abuses them, runs them completely dead, doesnt turn down the charger and drops them right back on @ over 1C just to put them right back in his truck to run them flat again....no issues, they are still going strong (enough for him, I use them when the track is slippery, they dont have much punch @ 20C/3600).

Joey,
you better teach your son to threat them right: you don't want him to get hurt. Those lipos can get real agressive

I'm really hard on mine (never balance, I mean NEVER..always charge at 2C, warm them etc) I do store them faithfully at 7.50 since puffing 3 at 8.40 for 90 days but I haven't had a failure since..

I know with my pan cars that run a 1s lipo having them overgeared has caused that before. It puts too high a load on them i think

ive had 3 packs do this also, thought it was due to being lazy with putting some charge back in

Charlie don't surf wrote:I do store them faithfully at 7.50

more info? I really havent read up on storing lipos, since I only race ocassionaly, this is probably something I should do

JK Racing wrote:

Charlie don't surf wrote:I do store them faithfully at 7.50

more info? I really havent read up on storing lipos, since I only race ocassionaly, this is probably something I should do

Just make sure you store them at 3.8 or 3.85/cell (3.75 works too but a bit on the low side it seems).

It's easy to do - from a fully discharged pack, put them in charge at 1C, monitor voltage per cell, when they are about 3.92V/cell then just stop it here. With an open circuit and after an hour or so, they then are in the 3.8-3.85V vicinity.

Now, of course, this assumes your don't use too wimpy packs for your application

Paul

Sorry to revive an old thread, but why are you guys so hard on batteries? They're not cheap, and it's not that hard to take good care of them. Why would you not balance? It adds 10 minutes to the charge time!

Lonestar wrote:It's easy to do - from a fully discharged pack, put them in charge at 1C, monitor voltage per cell, when they are about 3.92V/cell then just stop it here.

Since I only have "pack" voltage displayed, get it to the 7.85 range and pull it would be my best plan. Heck, most the times after a race it isnt even down that low.


I think all of my lipo failures (which isnt that many) is due to storing them fully charged. Never read up on them other than about over charging and over discharging, those were the 2 biggest red flags discussed to death about lipos.

talking heads did a song about lipos [youtube]xNnAvTTaJjM[/youtube]

85Edinger wrote:Sorry to revive an old thread, but why are you guys so hard on batteries? They're not cheap, and it's not that hard to take good care of them. Why would you not balance? It adds 10 minutes to the charge time!

Gens Ace 5000k saddle pack, $32- a charger (Comp electronics Turbo 35GFX) that will pump 25a- $429....ability to push a pack at 5c, build safe heat, and dominate 17.5 blinky? Priceless!