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Author Topic: Radiators Charge My batteries ?  (Read 8566 times)

Offline neilep

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Radiators Charge My batteries ?
« on: 20/10/2004 19:24:00 »
Hello Science Experts of Answer Giverness,

I've often heard that putting empty batteries on a radiator (a hot radiator) for an houror so recharges them, or prolongs their life....to be honest I can't be arsed this time to try it but I call upon your esteemed knowledge  base to confirm and establish this as a myth or not.....

Could it be potentially dangerous too ?

Your positively charged answers will be most welcome.

'Men are the same as women...just inside out !'


 

Offline tweener

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Re: Radiators Charge My batteries ?
« Reply #1 on: 21/10/2004 03:40:56 »
I don't know about prolonging their life, but warming a battery will speed up the chemical reaction that produces the electricity.  If the battery is weak, it will be a little stronger for a little while.

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Offline neilep

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Re: Radiators Charge My batteries ?
« Reply #2 on: 21/10/2004 12:05:22 »
Thanks John....so there is a little truth in what I heard....but clearly not enough to put into general practice.....however, the last few years I've also seen these battery rechargers come on the market that claim to recharge non-rechargeable batteries !!....any views on how good these are ?... with my three kids we get through an awful lot of batteries.



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Offline DrN

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Re: Radiators Charge My batteries ?
« Reply #3 on: 21/10/2004 12:57:55 »
I've seen people put batteries on bonfires - I'm sure they weren't trying to extend their life though. I wouldn't recommend it!! I guess it depends on how hot your radiator is!
 

Offline tweener

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Re: Radiators Charge My batteries ?
« Reply #4 on: 21/10/2004 17:30:16 »
I don't think I'd try recharging a non-rechargeable battery.  They tend to leak when you do that.  I'm sure that Jay or some other chemistry type can help with what the reaction is and why the battery shouldn't be recharged.

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Offline gsmollin

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Re: Radiators Charge My batteries ?
« Reply #5 on: 22/10/2004 02:02:35 »
On a cold morning, when your battery won't start the engine, warming the battery will increase its ability to produce electric current and start the engine. It does not change the charge in the battery, and will not recharge a dead battery. For the most part, heat is the enemy of battery life, so don't store your batteries in any hot place.

Primary batteries are not rechargeable. However, some primary battery's chemistry is similar enough to rechargeables so that one can recover a portion of a partial discharge. It is also true that rechargeable batteries do not ever perfectly recharge, and eventually go dead and will not accept any recharge. There are many electro-chemistries in use today in batteries, so some of the claims for being able to recharge primary batteries have a grain of truth. Here is the rub- you don't know which chemistries and under what circumstances. Since batteries are full of toxic and potentially dangerous chemicals, the safe thing to do is follow the manufacturer's directions. This goes double for lithium batteries, since the lithium is ultra-reactive.
 

Offline chris

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Re: Radiators Charge My batteries ?
« Reply #6 on: 22/10/2004 08:51:03 »
Batteries produce current by undergoing a chemical reaction.

When you complete the circuit by connecting a load to the battery you effectively collect electrons from one side of the battery and deliver them to the other. In the process chemicals which want to give up electrons (at the cathode) are oxidised, whilst chemicals that like to take electrons (at the anode (+)) are reduced. This process continues until all of the chemicals are consumed.

When the battery is new these chemicals are in excess; there are plenty of them bobbing around ready to donate and receive electrons to power your torch or mp3 player etc.

But as a battery tires the abundance of unreacted chemicals begins to fall and so the rate of reaction falls. Also, the internal workings of the battery get clogged up with the waste of previous reactions.

When you heat up your 'dead' battery the rise in temperature makes all of the atoms inside move around a lot faster and collide with other ions and atoms much more frequently and much harder. This greatly increases the chances of a successful 'collision' producing some electricity.

As a general rule, the rate of any reaction doubles for every 10 degree (C) rise in temperature. So for a dead battery, by heating it, you can push up the rate of reaction to close to what would be achieved at room temperature with a healthy battery, hence giving the impression that the battery has come back to life.

Chris

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Offline neilep

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Re: Radiators Charge My batteries ?
« Reply #7 on: 29/10/2004 19:52:05 »
Thanks everybody for your great responses....especially chuffed to hear my question being answered on the radio show too.....I'm so famous now, I'll have to get an agent *smug mode*:D

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Re: Radiators Charge My batteries ?
« Reply #7 on: 29/10/2004 19:52:05 »

 

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