Recharging 2016/2032's

[Sceadwian]

What prevents a CR2016/2032 type battery from being recharged? Forcing current through a battery in reverse (even a primary cell) is going to recharge it to some extent. I remember a company that years ago sold rechargers for common alkaline cells. What would the results be for atemping to recharge a coincell? Would you be able to get even a single 50% recharge?

 

[RODALCO]

Just give it a try.
You may get some charge in it.

It is important to limit the charging current to say 5 or 10 mA.
Put an LED and series resistor (47 Ohms) in series with your variable power supply and measure the current too.

These cells are 3 Volts, so carefully increase your charging voltage over 3 volts and measure the charging current.
With LED in series and resistor it may have to be 4.8 Volts ( 3 V + 1.7 V led + 0.1 V in R ).
Check that the cell doesn't get hot, otherwise it may explode.
if you get some success, that is great otherwise a flat cell was thrown out so no loss there.

 

[audioguru]

They are not rechargable battery cells. You don't want to be near lithium when it catches on fire. It burns with a very hot white flame like magnesium.

 

[k7elp60]

I agree with audioguru that form of lithium batteries are not rechargeable.
In fact they are considered potentially hazard and are shipped via ground and
generally the shipping cost a little extra.

 

[fingaz]

Based on previous experience, I would not recommend attempting to recharge Lithium coin cells. . . I have seen one 'explode' just by shorting it, so I'd hate to think what may happen if you apply a charging current

 

[Sceadwian]

I've seen lithium packs go before, I know what happens. These are however coin cells and I would never even consider recharging one without some kind of explosion protection around it. As far as fire hazzard, as long as it doesn't go shooting across the room into a tank of gasoline even a 2032 doesn't have the energy density to start a serious fire. Simple current limiting should suffice.

 

[Nigel Goodwin]

It's your choice, but's it's a silly idea!!!.

 

[Sceadwian]

The question actually became moot shortly after I'd asked it =) The reason I asked is because I had three 'micro photon' lights that mysteriously stopped working shortly after I took out the original blue/uv lights and replaced them with bright white LED's. I thought I'd aligned the leads wrong and drained the batteries, turns out all three LED's had mysteriously fried. They worked when I put them in and when I tested them a few weeks later they were toast. I must have put them somewhere where they got a decent zap, cause they're all fine now after careful replacement of the LED's. The other alternative is I reverse biased them with the two 2016's that power them. That puts about a bit over 6 volts which is I think above the maximum reverse bias of the LED's? I reversed them once or twice at least testing them because I couldn't remember if the short lead on the LED was the anode or cathode.

 

[audioguru]

It is difficult to determine how long a CR2016 lithium coin cell will power an LED because it is rated for a load current of only 0.1mA. A bright LED needs a current 200 times more.

The max allowed reverse voltage for most LEDs is 5V.

 

[RODALCO]

LED's

Sceadwian
LED: Anode is the longer terminal
LED: Cathode is the shorter terminal. it is also the flattened side of the LED casing.

As a safety measure to avoid popping a LED on reversed polarity i always fit a 1N914 or 1N4148 or eq. in antiparrallel with the LED.
It will avoid killing the LED and is cheaper to replace (US$0.03) than a couple of bucks for a super bright LED.

 

[Sceadwian]

I bought the LED pack from Hong Kong on E-bay. Like 25cents each for a 100 pack, and that was a year ago. I won't spend 5 bucks for the same thing from Radio Shack or elsewhere.

 

[audioguru]

RadioShack buys 100 cheap LEDs from Hong Kong for 25 cents then sells each LED for 5 bucks.
Digikey and Newark buy good LEDs from Agilent (Their LED division has a new name again but I can't remember it, it was HP before) and sells them for 50 cents each.

 

[rechargealkalineAA]

I am looking for info on charging the coin batteries

I have had very good luck recharging standard alkaline AA and AAA. I bought a Kodak charger from Wongmart, and I put standard AA's in it all the time. They don't get hot and if they are too used up to take a charge, the led blinks. They work a bunch of times.

I found this out from a broken Airsoft gun. The yellow "Ni Cad rechargeable batteries" were actually a bunch of chinese cheap alkaline AA soldered together. A lot of lantern batteries have AA or C/D batteries in them too.

What prevents a CR2016/2032 type battery from being recharged? Forcing current through a battery in reverse (even a primary cell) is going to recharge it to some extent. I remember a company that years ago sold rechargers for common alkaline cells. What would the results be for atemping to recharge a coincell? Would you be able to get even a single 50% recharge?

 

[rechargealkalineAA]

radioshat

Radioshack is awful. They should go out of business.

RadioShack buys 100 cheap LEDs from Hong Kong for 25 cents then sells each LED for 5 bucks.
Digikey and Newark buy good LEDs from Agilent (Their LED division has a new name again but I can't remember it, it was HP before) and sells them for 50 cents each.

 

[rechargealkalineAA]

Interesting.

I had a chinese 2 AA flashlight that shorted out today. I picked it up and it was very very warm. The metal strap and switch that went from the battery - to the - on bulb holder was acting as a heating resistor like an oven coil.

They are not rechargable battery cells. You don't want to be near lithium when it catches on fire. It burns with a very hot white flame like magnesium.

 

[rechargealkalineAA]

I don't think it can explode. Burn maybe. How did it come to explode? Was it in a watch or electronics item?

Based on previous experience, I would not recommend
attempting to recharge Lithium coin cells. . . I have seen one 'explode' just by shorting it, so I'd hate to think what may happen if you apply a charging current

 

[audioguru]

Radioshack is awful. They should go out of business.

RadioShack went out of business in Canada a few years ago. Circuit City in the US took over some of the stores and called them The Source. They sell cell phones, cheap electronic toys, computer accessories and digital cameras.
Circuit City is bankrupt now.

 

[currentguna]

hai please us e something in the circiut

 

[fingaz]

I don't think it can explode. Burn maybe. How did it come to explode? Was it in a watch or electronics item?

If you don't believe they can explode by being shorted, feel free to try it (I am in no way recommending this action. If you don't wish to injure yourself, do not try this).
Short out a battery, and you cause lots of current to flow directly from one terminal to the other. What happens to this current?? It is converted into HEAT. If you heat anything flammable in a sealed enclosure (inside the battery casing) it will explode.

I tried this out of curiosity (and my destructive nature ) That's one experiment I won't be trying again

There were a lot of 'issues' relating to the charging of lithium ion batteries in laptop computers. and causing fires. I saw a vidoe on youtube recently of a laptop (lithium ion) battery causing a fire whilst being charged. It certainly went with a BANG, so not just a fire. Can't find that particular video now. . .

I'm not saying that EVERY lithium battery will explode if it is recharged or shorted, but for the price of a cr2032, is it really worth risking it?

Neil