NiMH AA's rated for 13.5 Amp drain

[lemlux]

NiMH AA\'s rated for 13.5 Amp drain

I recently noticed that PowerStream, the popular (to CPF) provider of the fighting robot 98 Amp rated 1/2 D 2500 mAh Nicads also offers the following:

AA's 1500 mAh rated at 9C (= 13.5 Amps)

These must be special order purchased in minimum quantities of 100 @ for edit $194, not $124 as a part of a $200 minimum order.

Do any of you MR16 project etc. people find this to be an attractive current handling vs. capacity tradeoff?

 

[Illuminated]

Re: NiMH AA\'s rated for 13.5 Amp drain

Lemlux,

Good find! I'll have to check those out. If they're anything like the 1/2D's as far as low internal resistance, they'd be perfect for many applications...

Thanks - John

 

[paulr]

Re: NiMH AA\'s rated for 13.5 Amp drain

Sounds interesting, though the MRC16 mod I've been wanting to try involves ten 1/2D battlebot cells and a 6D Mag.

 

[freewheelin']

Re: NiMH AA\'s rated for 13.5 Amp drain

If there's a group buy I'm in.

 

[FalconFX]

Re: NiMH AA\'s rated for 13.5 Amp drain

These guys are supposedly rated to a discharge of C10...

http://www.batterieswholesale.com/nimh.htm

(go down to the Industrial Fast Charge/Discharge flat tops)...

 

[Klaus]

Re: NiMH AA\'s rated for 13.5 Amp drain

Seems like a very good find and thanks to Lemlux for it

Regarding the MR16 usage those look like fitting the bill to perfection for 12 cells and 35W and up bulbs for peoplke more concerned about brightness than runtime and as was tested the standard NiMhs won´t properly support more than 20W when used with 12 pcs and 35W need 24pcs already.

I still would be interested in more data on expected voltage drop under 1C, 2C, 3C etc loads - the "standard" NiMh do support 2C as per the data sheets but voltage drop is so significant above 1C that its not usable anymore.

Klaus

 

[Ginseng]

Re: NiMH AA\'s rated for 13.5 Amp drain

I would be interested in at least a dozen for an MR16 build. 1800 mAh at 9-10A drain would be more ideal though, wouldn't it?

Wilkey

 

[lemlux]

Re: NiMH AA\'s rated for 13.5 Amp drain

Ginseng:

I suppose I could ask Powerstream what tradeoff options exist for AA's between current handling capability and capacity. Their website invites just such questions.

If I were to organize a group buy, I don't think I'd want to hassle with individual mailings of < $50.

 

[PaulW]

Re: NiMH AA\'s rated for 13.5 Amp drain

Lemlux,

I have some plans for the future that could use some of these. If there were a group buy, that would entail a minimum of approx 40 AAs for $50 for each participant.

I also am interested in hearing about what Powerstream has to say about tradeoffs.

Here is what I'm thinking now: IF the rating does hold at about 2C to 3C, and IF you're willing to do a group buy for us, I would be willing to buy 40 of them or maybe even a tad more . . . IF I can persuade Wilkey to buy half of them from me (Wilkey: I'm thinking I would like to have 24). That's a lot of ifs, but this is the direction I'm going in.

Paul

P.S. (Edit) Do you know if these Powerstream 1500s will fit in the 4AA to D adapter that Chief Wiggums is developing?

 

[lemlux]

Re: NiMH AA\'s rated for 13.5 Amp drain

First, an Apology:

I read the wrong line on the chart. The batteries in question are $194 per 100, not $124 per hundred.

Mark at Powerstream told me that the xC rating doesn't imply any specific voltage drop curve. It merely shows the maximum safe xC continuous discharge rate the cell can be run at without inducing a capacity reducing discharge through the vents.

He said he will try to get me voltage drop characteristics for these cells at 2.0 Amp, 3.0 Amp, and 4.0 Amp levels.

Simply put, the higher current handling cells have thicker conductive foil layers which leave less room for power generating materials.

Mark said that PowerStream doesn't do much with hobbyists other than their 1/2 D NiCad cells and their 800 mAh 4/3 AAA cells which also handles high current discharges well.

 

[Snewt1]

Re: NiMH AA\'s rated for 13.5 Amp drain

Someboby group buy these things!!!

I'll take 24!!!

Hmmmmm.....50W IRC MR-16 in a 3D mag.... /ubbthreads/images/graemlins/cool.gif