High current AA NIMH cells

[xeonsaga88]

Hi , i have been searching around the forums and i have only seen Titanium 1800 and Elite 1700 Cells. But has anyone tried the tenergy 2000mAh 10C High rate drain cells? (http://www.all-battery.com/aa2000mah10chighdrainhighcapacitynimhrechargeablebatteryflattop.aspx)

I was wondering how well will it perform under 10+Amps load.

 

[lolzertank]

Definitely get the Elites. They can handle 30 amp loads without dropping below 1V.

 

[Illum]

elite1700s are a bit picky on series chargers...so keep that in mind if your intending to build a hotwire with them.
I used 9 of them with a mag85 and while the performance was awesome it frequently cooks at high temperatures using battery junction hobby chargers. I had to charge mine individually using NiMH chargers. Eneloops did not give me any of the symptoms above, and I'm operating 3 Mag85s and 1 ROP on eneloops with no issues.

Eneloops can comfortably give 10 amps with no issues...but that's more of a shorting current. Actual usage I'd keep it around 4 amps max [2C]

 

[45/70]

Not speaking from personal experience except for Elite 1700's, but from what I've heard, the Titaniums, while performing quite well, have a higher incidence of leaking. Add to that the rather questionable reputation of Tenergys here on the Forums, I'd stick with the Elites.

Eneloops can comfortably give 10 amps with no issues...but that's more of a shorting current. Actual usage I'd keep it around 4 amps max [2C]

I have a thing about my hotwires. I like 'em bright and white. "Damn the torpedos, full speed ahead"! :devil:

Dave

 

[Illum]

oo:...well um...in that case

 

[TorchBoy]

Eneloops can comfortably give 10 amps with no issues...but that's more of a shorting current.

I thought Eneloop shorting current was up around 17 amps. :shrug:

 

[Illum]

I thought Eneloop shorting current was up around 17 amps. :shrug:

comfortably yes....I didn't say what maximum was, I am not capable of measuring higher

 

[45/70]

oo:...well um...in that case

Yeah, well, OK. Since the OP was asking about high current AA cells, I just thought your comment seemed to suggest that eneloops were an amicable solution. You really didn't say that, so my apologies.

While the eneloop is equal to, or in most cases, superior to standard NiMHs when under a heavy load, compared to a high discharge rate cell like the Elite 1700, their performance is poor, over about 3A current draw.

Dave

 

[SilverFox]

Just to add a general comment...

If you charge Eneloop cells on a 15 minute charger, and discharge them immediately after charging while they are still hot, their performance increases sharply.

On the other hand, if you charge the Elite cells at 1.5 amps and let them rest for an hour after charging before running the discharge test, they will fall flat on their face at 30 amps.

Keep in mind that the 30 amp results were obtained immediately after charging at 2C and while the cells were still hot.

We ran into similar results while testing the CBP 1650 cells. They performed much better hot off the charger, then after they had rested and cooled down for awhile.

Tom

 

[bcwang]

Tom,

Do you happen to have the test results of the elite 1700 anywhere? I don't see them on the nimh charts nor anywhere else.

 

[45/70]

Tom,

Do you happen to have the test results of the elite 1700 anywhere? I don't see them on the nimh charts nor anywhere else.

I'd like to see Tom's results, if he has them, as well. In the meantime bc, CBP does have this graph.

Dave

 

[SilverFox]

Hello Bcwang,

Sorry, I haven't tested the Elite 1700 cells.

Tom

 

[bcwang]

Hello Bcwang,

Sorry, I haven't tested the Elite 1700 cells.

Tom

Oh, too bad. I thought from your comment below that you had tested it.

On the other hand, if you charge the Elite cells at 1.5 amps and let them rest for an hour after charging before running the discharge test, they will fall flat on their face at 30 amps.

 

[LuxLuthor]

Cheapbatterypacks.com has a run plot here. They are tested under absolutely the best possible scenario...namely fresh charged, HOT, and with leads from Competition Electronics CE-35 soldered directly to cell.

I have lost at least 20 Titanium 1800 cells to leakage under normal use, and will never take a chance on them again. These Elite 1700mAh cells are the only AA High Current cell I would use if I want sustained output >7A.

Under 6-7A, I would consider the Eneloop.

 

[bcwang]

Cheapbatterypacks.com has a run plot here. They are tested under absolutely the best possible scenario...namely fresh charged, HOT, and with leads from Competition Electronics CE-35 soldered directly to cell.

I have lost at least 20 Titanium 1800 cells to leakage under normal use, and will never take a chance on them again. These Elite 1700mAh cells are the only AA High Current cell I would use if I want sustained output >7A.

Under 6-7A, I would consider the Eneloop.

Those graphs look pretty awesome. Do these cells have any poor attributes about them? Bad self discharge rate? Runs worse than eneloop when cold? Poor cycle durability? Sizing issues?

 

[LuxLuthor]

Those graphs look pretty awesome. Do these cells have any poor attributes about them? Bad self discharge rate? Runs worse than eneloop when cold? Poor cycle durability? Sizing issues?

Yeah, all of the non-Eneloop technology high current output cells have faster self-discharge rates sitting idle, so you need to manage that. It will still dramatically outperform the Eneloop at higher currents, (hot or cold) as long as it has been charged within a reasonable time. Sizing is great. Not 100% sure on cycle life rating. They both have their strengths and weaknesses. If I could only have ONE AA cell on a desert island, it would be the Eneloop.

 

[TorchBoy]

Re: High current AA NiMH cells

I'd like to see Tom's results, if he has them, as well. In the meantime bc, CBP does have this graph.

It's hard to believe Tom hasn't been scrambling to test them.