Check battery charging progress

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how i can check the capasity of charging of my dc dry battry
i want to check the %age of charging of my dc battry at any time
how much enerygy is consumed and how much remaining
how it is possible?????????????????????????????????

 

[(*steve*)]

If you look at the datasheets for the battery, you will find a graph that shows voltage over discharge and you can use this (works better for some battery chemistries than others)

 

[KrisBlueNZ]

Is it rechageable or not? A "dry battery" or "dry cell" is normally not rechargeable.
In either case, it is difficult to estimate the energy remaining in a battery. To do a reasonable job you really need a smart device that can monitor current into the battery (for a rechargeable battery), current out of the battery, terminal voltage, and probably temperature. There are ICs designed to do this - try googling Benchmarq (I think they've been bought out by Texas Instruments). Microchip do this sort of thing too I think. Google "battery energy monitoring circuit" or something like that.
If the battery is rechargeable, you may already need smart circuitry for controlling the charging process; this circuitry may also be able to monitor the current drawn from the battery and estimate its condition.
Also, as Steve suggested, you may be able to get a fairly approximate indication of charge level by looking at the terminal voltage, provided that you either know the load on the battery or can temporarily remove it, since the terminal voltage is affected by the load on the battery at the time you measure it.

 

[[email protected]]

plz help

I want to recharge my 6 v 3 ah dc battry
how much the maximum voltage should i give to the battary that it will charg in minimum time

 

[GreenGiant]

its not the voltage that you want to change, you want to apply a straight 6 volts to it while charging

You want to change the current that you put into it, apply 1 amp it will charge in about 3 hours, 3 amps 1 hour, 6 amps and it will charge in about half an hour

the one concern here though is that you need to find the max charge current for the battery, and DO NOT EXCEED IT, this can cause fire, or explosion

 

[BobK]

its not the voltage that you want to change, you want to apply a straight 6 volts to it while charging

You want to change the current that you put into it, apply 1 amp it will charge in about 3 hours, 3 amps 1 hour, 6 amps and it will charge in about half an hour

the one concern here though is that you need to find the max charge current for the battery, and DO NOT EXCEED IT, this can cause fire, or explosion

Can you please explain how one controls the current while maintaining a constant voltage? (hint: it is not possible).

To charge a battery you typically need a couple of volts higher than the battery's voltage. Normally you want to control the voltage to supply the desired amount of charging current. To charge at a constant current, the voltage will have to start out low and rise as the battery get's closer to chared. There are various methods of determining when it finished depeding on the battery chemistry. I built a NiCad charger, and in this case, the battery is fully charged when the unloaded terminal voltage drops after having risen during the charging cycle. A sudden rise in temparature is one of the best indicators that charging is complete, so really good chargers incorporate a thermistor that is in contact with the battery and monitor its temparature.

Bob