hey...
i am going to work on a project and for that i require to give the supply from the 9v rechargeable battery and want to recharge it back without removing it from the project.
so can you guide me how to charge the battery.......
thankz
So you have a "9v rechargeable battery"? What type of battery is it? How you charge it depends on what it's chemistry is. A link to a specification would be good.
Often the best way to charge batteries without removing them is to arrange a charging socket that disconnects the battery from the circuit. Or do you mean that it needs to carry on providing power to the project while you are recharging it?
Steve
Most of the batteries are charged by voltage 10 - 15 % than nominal battery voltage, with current limit 10% of the capacity of the battery.
ted:
Most of the batteries are charged by voltage 10 - 15 % than nominal battery voltage, with current limit 10% of the capacity of the battery.
Except if you try that with most lithium-based batteries there's a fair chance of burning your house down.
Steve
Maybe you do, not me. Quick battery chargers can charge battery with the current much higher.
ted:
Most of the batteries are charged by voltage 10 - 15 % than nominal battery voltage, with current limit 10% of the capacity of the battery.
Would you claim that ALL batteries can be (safely) charged in that way?
srnet:
Would you claim that ALL batteries can be (safely) charged in that way?
Yes
Quick battery chargers sense the temperature of the battery, when it is to high charging is stop until battery is cool down, so temperature is crucial factor telling about safe charging.
One of the problems of the internet is that any idiot with no real idea what he's talking about can turn up and give "advice" which is positively dangerous and could result in serious damage to people and/or property.
I guess we just have to hope that the weight of sensible advice persuades people not to endanger themselves.
Steve
Now you are #1 on the list of smart pants.
I'm with slipstick on this, ted. Your comment shows little consideration for battery chemistry or overall reliability or safety Different battery chemistries require different charging techniques. For instance:
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OK to indefinitely trickle charge a NiCad at C/10, but you risk driving off all the hydrogen from a NiMH battery if you do that. Lithium I'm not as familiar with, except that charging one is even more specific in the requirements (for Lithium chemistries, I rely on off the shelf solutions).
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Negative Delta V is a good technique for terminating a fast charge on a NiCad, but, with a NiMH battery, this is more difficult, because the dip in voltage is much less, so is harder to detect.
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Delta T is another good way to terminate a charge on a NiCad, especially because while the battery is charging the reaction is strongly endothermic-the battery cools during charging. Less so, with a NiMH, but this is still a good technique for terminating a charge on a NiMH. In fact, when charging a NiMH battery, it's a very good idea to monitor the temperature, because when the temperature goes up, that means the battery is fully charged, and electrolysis is occurring. If the battery is allowed to get too hot, hydrogen will vent from the cell, depleting it's capacity.
And so on. In some cases incorrect charging will, merely result in reduced capacity and/or longevity. In other cases, as slipstick pointed out, it can be downright dangerous.
BTW: I, too, would like some "smart pants" ;D
That is your theory, I am talking about practice, battery ever exploded when I charge it by 1/10 of it capacity ......
I think ted still has a lot to learn.
The first thing is to not give bad advice.
You can't compare NiCad or Lead-acid, that can be or even likes overcharging, to NiMh or Lithium, that shouldn't be or is dangerous when overcharged.
Maybe ted should study this website.
Leo..
ted:
That is your theory, I am talking about practice, battery ever exploded when I charge it by 1/10 of it capacity ......
You're still not saying anything about what battery chemistry you're talking about? Or how long you're applying this charging current. Or do you mean ALL battery chemistries? And at any length of time? And, when you say this, are you discounting quality of charge? Sure, you can get away with charging a "battery" with C/10, but there are a lot of things that escape an empirical examination.
And, the things I said about proper charging procedure, come from battery manufacturer recommendations, and from engineering documents. You can base your designs on empirical "data" alone, but, eventually, you're gonna pay the price.
Wawa:
I think ted still has a lot to learn.
The first thing is to not give bad advice.You can't compare NiCad or Lead-acid, that can be or even likes overcharging, to NiMh or Lithium, that shouldn't be or is dangerous when overcharged.
Maybe ted should study this website.
Leo..
.Study yourself, I have no problems with my battery
ReverseEMF:
Or how long you're applying this charging current.
Just one example.
3.7 battery,charger voltage supply 4.2V, current limit 600mA, battery is stop taking the current from power supply when reach 4.2V
The end of my discutions.
ted:
Just one example.
3.7 battery,charger voltage supply 4.2V, current limit 600mA, battery is stop taking the current from power supply when reach 4.2V
The end of my discutions.
Well, OK, in this case it sounds like you're charging a particular kind of Li-ion battery. But, you're still not actually saying what chemistry you're talking about. So, it gives the impression that you think all chemistries can be optimally charged in the same way.
Recharging can be done either manually - by a switch that can reverse the connections (I do not remember its name, but is used to reverse the motors) or automatically:
a) detection of lower voltage module
b) electronic switch module
c) power supply unit.
I think one may want to use LiIon units. Then is is very handy to look into their datasheets. For instance, this one: