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NiCd discharge curve

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Hello everyone. I'm looking for a discharge curve (V vs time or V vs. current) for a NiCd cell at preferably a large capacity. The best curve i can find now is for a 4Ah capacity battery discharging at 800mAh for 5 hours. I need to find one with a larger capacity and larger current for approx. the same time (5 hours). Thanks

-jay
 
Ni-MH rechargable cells have replaced most old Ni-Cads, but some companies still make some big ones, like SAFT. Their website probably has detailed datasheets for them.
 
NiCds are also banned in Europe, under the RoHS legislation.
 
I don't know about that. I work in a defence company and even though some of the vehicles go to war and fire weapons containing all manner of harmful compounds we still can't use cadmium plated connectors!
 
Yes, RoHS is fairly new and it doesn't affect designs already in production.
 
Since when were NICds banned in Europe? I thought ROHS excempted battery technologies like NiCds and lead-acid because there is no substitute for them (it's not like you can have iron-acid or NiCu batteries).
 
Ni-Cads are older than the hills. They have been replaced with much higher capacity Ni-MH cells for many applications. Energizer doesn't make Ni-Cads any more, their 2500mA/hr Ni-MH cells are way better than their old 650mA/hr Ni-Cads with the same AA size.
 
It would be ironic and idiotic at the same time if ROHS alowed NICAD and lead acid batteries to be exempt completly, as a single large Lead Acid Battery has more lead in it than a few ten thousand PCB's plated in tin lead solder. Ni-Cad's still can't be replaced it heavy discharge applications. 2500ma NMH might beat 650MA hour Nicads per power unit, but their number of recharges is significantly lower.

There is a reason why specific cell chemistrys are used in different applications. The fundamental behavior of the materials themselves lend themselvse to one application or another. Nicad's beat NiMH in power delivery PER UNIT AREA. NiMH's beat Nicads in power density per unit area. Li-poly's beat them both but the physical construction of the cell's is complex and thermal runaway is a real problem (Sony recently recalled more than 9 million units) All of these issues are in constant debate as the battery industry evolves (lipoly will reign supreme eventually it'll just take till the physical structure managment and optimization reaches what have already been developled for existing chemistries, at that point I'm sure active power generation units (Fuel cells and micro turbines) will be viable options for new power and the whole cycle will start again.

Oh and as the OP actually asked about it.

https://shdesigns.org/batts/battcyc.htm

That's the first hit you find looking for NICD discharge curve on google.
Try looking before you ask.
 
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Lead acids aren't banned because there are many recycling programs around. To be honest on second thoughts I'm not that sure about NiCads. I think it depends on the nature of the appliance and how it's disposed of. Most people will just stick a cordlesss electric drill in the normal rubbish bin, but far fewer people will do the same with a car battery.
 
There's a facility not far from here that recycles car batteries, it's an old lead mine and smelter, and has been recycling lead for decades. In fact my wife used to live about a mile away as a child, and all children were provided free milk by the facility. Milk helps prevent possible lead poisoning problems in children, and there are also sensors all over the local environment, monitoring the lead levels.

As far as I'm aware there's never been any problems with lead levels, and the free milk was more a political act than anything else!.
 
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