Battery Problems

[obrien]

I am not sure what has happened yet, so I am looking for some help here.
My first battery back yesterday was a pair of venom 3000s. I had just finished making a few passes, brought it in, set it on the stand, and as I was opening the hatch, boom one of the battery packs blew up. Well I cleaned all of that out, let it cool down for a bit, and put in my set of tenergy 7 cell 4200s. I ran that around for about 3 or 4 minutes and then it died. Once back in, I looked everything over, it all seemed fine, so I put in the trinity 4200 6 cell packs after letting it sit for a few minutes. I turned it all back on, every thing worked fine.

Well tonight I see that a wire came off of one of the cells in my tenergy pack, and one of my trinity batteries appears to have become really hot. Then end cap is slghtly melted.

The boat has a hydra 120 esc, ammo 36-50-2300kv, and I was running an octura x642, and switched to the stock prop on the very last run. The trinity's were run on both batteries.

Any help would be great. I am going to start with resoldering my battery connections since they are not that great. I am a newb at this so I need more practice.

[Avanti]

as long as you are redoing them turn them to side by side wit bars

[obrien]

yeah I think I just need to do all of my packs. I just concerns me that I am having problems with everything. I have some other props to try and see what happens. I should have my data logger soon. Then I can see what exactly is happening.

[ReddyWatts]

I would not use the Tenergy NiMH battery packs in a setup that uses more than 50 amps.

[Avanti]

readywatts can you elaborate on that. obrien and I are both fairly green when it comes to amps used and brushless motor requirements. when we were into rc back in the day, there was none of this to worry about so we are in a learning process with all the new stuff.

[obrien]

is it the cells we have to worry about, or connections?

[ReddyWatts]

The Tenergy packs use very thin connecting tabs. They will get hot enough to melt the solder on the wire connections and your battery temps will get very hot. The cells have a higher resistance and you will not get as much speed out of them as an IB3600 cell. Buy cells with the heavier connection bars if running over 50 amps. The Tenergy cells are not as durable or designed for the higher current. Most brushless Fiegao motors will use from 50 to 100 amps depending on the windings and prop.

I have some 3300 tenergy cells that have lasted for a long time but I am now only running them on 700sc motors. 35 to 40 amps.

[obrien]

I will just plan to rebuild all of my battery packs and make sure they are right.

[domwilson]

I had problems with the Tenergy packs as well. They got hot and wouldn't deliver enough current. Went to battery bars and they seem to hold up that way. They don't get hot anymore. When I disassembled the packs, the tabs were very thin and easy to remove. They are just tacked on with 4 small points of contact. If they get wet, it rusts and increased resistance. At least in my case, I didn't even see the rust until I pulled them apart.

[obrien]

that might be what the problem is with my trinity batteries since they were in the boat when it went over a couple of weeks ago.

I quess I just have some soldering to do. lol

[sjslhill]

Be sure to use a volt meter to check each cell....in today's world, NIMH cells can just go to zero volts at anythime. I have 5, 4500mah cells that were charged up two weeks ago and now read 0 volts

[obrien]

I will be sure to check that when I get to rebuilding the packs.