NiCd battery or lead acid battery

[arbil]

Which battery is better , Nickel Cadmium or Lead acid .If we want to replace an existing NiCd battery bank with lead acid , what are the factors we would have to consider ?

 

[ScottyUK]

'Better' based on what criteria?

Flooded NiCad calls have a better temperature range and should have a longer service life than a similar capacity flooded lead-acid, but will cost three or four times as much.

Charging characteristics are very different so you should look at the charger and determine whether it is suitable or can be reconfigured.


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If we learn from our mistakes I'm getting a great education!

 

[arbil]

Well exactly ,I have to replace an existing NiCd battery bank . However I don't know whether I should go for NiCd and incur extra cost or simply go for lead acid which I suppose will require more maintenance but save me lots of initial spending.This is considering that charger will be suitable.

 

[ScottyUK]

So... what is the duty? And in what environment? A battery holding up a nuclear power station's critical services board typically warrants the highest performance that can be obtained; in the case of a battery supporting a commercial building's UPS it is easier to make an economic case for a cheaper battery. A starting battery for a diesel fire pump in a cold climate justifies a NiCad, certainly in the eyes of the insurers - I had this discussion a couple of years ago when I got the price for replacement of the NiCad pack!


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If we learn from our mistakes I'm getting a great education!

 

[MikeHalloran]

The most natural application I can think for NiCds is helicopter starting batteries. They have to drive an electric motor to spin a big rotor up to a substantial speed before the turbine engine will even think about starting. There's just enough energy stored in a battery to do that, once, and maybe twice if you are real lucky. After which, the battery is literally exhausted and will take a full charge and hold it for quite a while.

The worst application for a NiCd is any 'float' situation, where you take out a little energy, then add a little, repeat ad infinitum, and never fully discharge the battery... under which condition a NiCd eventually loses all of its capacity

Lead-acid batteries are almost exactly the reverse; they don't like being fully discharged, and don''t mind floating indefinitely.

So, as has been said, each is 'best' for something, but neither is best for everything... and there's probably a good reason why NiCds were selected for your application, whatever it is..


Mike Halloran
Pembroke Pines, FL, USA