Max NiMh D-cell current?

rayman

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I'm thinking about putting my SST-90 in a 6D Maglite with 6x NiMh D-cells. I never used D-cells in a high-current application especially not D-cells. I saw lots of graphs about AAs but I didn't find any about D-cells. So can I use a 10Ah NiMh D-cell for this mod? How do they handle the 10A?

rayman
 

McAllan

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If I remember correct the SST-90 has a max of about 10 A.
Driving it with a resistor is a waste of power. You need a driver and so the actual current will be much less - nearly half.

But to answer your question. I don't know any NiMH cells which have troubles delivering 2C. You need 10 A which with your chosen cells is only 1 C - no problem at all.

The maglite switch however might get into trouble if you're just driving it with a resistor. If I remember correct the stock switch is good for around 5-6 amps.
 

rayman

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I know. I'm waiting on one of the drivers right now ;). I only want to know if the can handle the current.

thanks
rayman
 

Mr Happy

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A high quality 10 Ah NiMH D cell can deliver 10 A without breaking a sweat. Keep in mind that if you put six of those puppies in series they can deliver a lot of power. If you should accidentally make any short circuits there will be enough current available to melt most wires and metal connections you might be using. Treat a pack like that with a goodly amount of respect.
 

VidPro

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yup handle the 10a, but they warm up a bit too.
my packs that are in belt holders are slightly insulated and at 10, it gets pretty warm inside, after 1/2 hour.
so anything run with that much chemical energy transduction is going to add in heat to your thingees, so just take that into account.
at 2A the heat comming out of them is not concidered, at 5 it warms, at 10 it warms up good.
 

mdocod

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I've tested some crappy Tenergy D NIMH cells out to ~30A and they do fine but with some sag.

Use a proper regulator and it will be really decent.

FYI: a SST-90 running at 10A from a set of 6 NIMH cells in series will result in a current draw from the cells of more like only 5A. Provided it is regulated properly.


Eric
 

rayman

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I know that this will be a lot of power but I'm always checking the connections twice in my mods. I also won't drive the SST-90 at 10A for long terms. Didn't know that it would only draw about 5A but thinking about it right it's obvious as the voltage is about twice the needed voltage the current is about half the needed current.

Edit: I'm planning on using this Ansmann 10Ah NiMhs, did anybody make any experience with them? Made only good experience with their chargers.

rayman
 
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McAllan

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At least consider their LSD variant (low self discharge).
Not very long after charging the non LSD will have same capacity as the LSD ones and hereafter it's totally win for the LSD.
I'm considering changing some older but otherwise fine working NiMH to LSD out of pure convenience.
 
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