are 20 2500mah NiMH batteries really equal to a 50 amp hour lead acid scooter battery?

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mikestevens1
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are 20 2500mah NiMH batteries really equal to a 50 amp hour lead acid scooter battery?

I need to power a water pump at a cabin in a remote location charged by solar panels and a lead acid batter would be impossible to pack (by me anyway) in due to it's weight.

The wieght of 20 AAs is nothing. I cannot go higher like D cell because I am in Canada and all batteries higher than AA have the same NiMH (what a scam).

By simple measurements - each AA NiMH battery is 2500mah or 2.5 AH x 20 = 50 AH but something tells me this will not be the same as a deep cycle lead acid battery?

Also, once they are all hooked up properly in parallel + series to equal 12 volts, can they be charged in a bundle like this?

Any help on this is greatly appreciated.

thanks!

Johnny J
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Re: are 20 2500mah NiMH batteries really equal to a 50 amp ...

20x2500mAh = 1.2V 50Ah, if you need 12V 50Ah you have to use 200cells.

Regards

Johnny

reikiman
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Re: are 20 2500mah NiMH batteries really equal to a 50 amp ...

Further the recommendations I've seen on NiMH cells is to not parallelize them to this degree. The statement I've seen several times is it's safe to make a NiMH pack with 2-3 parallel strings but no more than that. Maybe someone like Aerowhatt who's done more of this can comment further?

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NickF23
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Re: are 20 2500mah NiMH batteries really equal to a 50 amp ...

don't parallel charge nimh (google for more info). Nickle based batteries also don't much like constant trickle charging anyway many failed consumer batteries are damaged quite quickly by this sort of setup for example rechargable keyboards/toothbrushes/shavers etc so its a bad choice for solar recharging. SLA is a better choice and can paralled easily, don't forget the voltage regulator. If you want something lightweight try lifepo4 with a good bms. For example ping battery or lifebatt.

fisher727
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Re: are 20 2500mah NiMH batteries really equal to a 50 amp ...

I have an off grid house powered by solar panels. Power is stored by a set of 48 6 volt Silicone lead batteries. I pump water with a 48 volt submersible pump. Currently it is common to pump water using solar panels direct to the water pump motor, no batteries needed. This is an option you might consider. Batteries should be avoided if possible for pumping only water especially if you do not have any other need for electrical power. If you need electrical power, lead batteries are you best bet. There are smaller lead batteries made for solar applications that you could pack in.

Eric Fisher
www.SiliconeBatteriesUSA.com

Mik
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Re: are 20 2500mah NiMH batteries really equal to a 50 amp ...

Do you absolutely need "on demand" electrical pumping power, or could you pump "as available" to a higher location and then gravity feed your water?

This information may be used entirely at your own risk.

There is always a way if there is no other way!

dogman
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Re: are 20 2500mah NiMH batteries really equal to a 50 amp ...

I know you don't want to pack lead, but maybe over several trips, you could pack in smaller sla's and paralell them. If you have money, then a 12v lifepo4 would be the lightest thing avaliable.

Be the pack leader.
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mikestevens1
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Re: are 20 2500mah NiMH batteries really equal to a 50 amp ...

great info

I came to the right place. All this good info in so little time!

I knew I had it wrong, and I thank you all for averting a huge waste of my time and money.

If in a remote location, the best pump ever, if you have a creek with drop off is a 'ram' pump that uses all the force of intake water & concentrates it on 1/20th of the water which then has immense pressure and high head.

But my geography wont work for this.

I'll have to take a look at lifepo4

thanks very much.

cheers

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