Rechargeable battery time again

penyekz

dc wrote:

They should work in your mouse, my mouse is OK even with the Poundland NiCads which are only 800mAh. Does the mouse led flash? and have you tried the Aldi batteries in a torch?

Looks like the ones you tried are not being charged by your Hahnel, could be a contact prob on the Hahnel charger. Or maybe the batteries are duff. Have you tried them all?

I too, like doozeruk, have had batteries that that are not standard shape and will not make contact properly in some devices because the shoulders or a bit of plastic gets in the way, by holding the +ve pip away from the contact.

You're brilliant m8! Tried to stick a thick piece of paper to move one of the contacts and voila! led starts flashing! now to figure out a way to get the contacts touching one another.

Its strange how it looks like its touching. These batteries are really strangely shaped.

yezdi

ollyk wrote:

I know the memory effect but 1. would you have 500mAh NiMh or 1.5Ah NiCd? 2. there are some who suggest that the memory effect isn't as bad as has been made out - it is generally reversable and if you discharge a rechargeable too much to the point of polarity swap then battery is !!!!!!ed NiMh or whatever!

We get 2700 mAH NiMh (in AA size) now that is 2.7AH. The largest AA NiCds that are available are a paltry 950mAH ie a third the capacity of NiMhs. Could you please let me know where we can get 1.5AH NiCds in AA size ? My choice is NiMh irrespective of the few advantages NiCds offer.

dc

On the NiCad v's MiMh debate, NiCads are the poor relation.

They leak over time, they regularly become short circuit because the slivers of metal in the electrolyte short together and if not used the charge leaks away ( never-ready when you need them).

I have had dozens of faulty NiCads, no faulty Nihms.
Technology has progressed, why buy the old (unless its at Poundland ).

matty_c608

You need a good 800maH for running those little MP3 Players off!!

Rarely you can find over 1000maH for AAA Batteries

quoia

matty_c608 wrote:

You need a good 800maH for running those little MP3 Players off!!

Rarely you can find over 1000maH for AAA Batteries

Sorry but this is meaningless.

If an MP3 player works on rechargeable AAA cells then the capacity of them ONLY has a bearing as to how long the unit plays for.

For example - if the 800mAh cell(s) last for 4 hours, then 400mAh will work perfectly well but only for 2 hours. Similarly 1200mAh would last for 6 hours.

How long a battery lasts depends on a) how much current (measured in milliamps) you draw from it and b) the amount of charge (measured in milliamp-hours) it has. A milliamp-hour is the amount of charge that is removed after drawing 1 milliamp of current for 1 hour.----So, for example, if a battery has 500 milliamp-hours, you could draw a current of 20 milliamps for 25 hours, or a current of .5 amps for one hour, or one amp for half an hour.

Stompa

FWIW I've just fully charged a new set of 4 AA's using my Maha charger - took about 4.5 hours.

Rave

I charged two of mine up using my Lidl quick charger (although I forgot to check how long it took, probably less than 2 hours though). The batteries only got warm and are now powering my Mini-Maglite absolutely fine.

yezdi wrote:

If you just do a search in google for memory effect in Ni-Cd batteries you should see a million pages explaining this. A couple of examples for your benefit:
Memory effect 1
Memory effect 2

Yes, and both of them say pretty much the same thing as the article I linked to, which is that there is no such thing as memory effect in consumer NiCd batteries, but there is such a thing as voltage depression.

I know that the manufacturers of Ni-Cd batteries would contest the above but from experience I have no doubt that this is true. My Dect phone came with Ni-Cd batteries. In one year, the phone simply did not charge any more. I replaced the Ni-Cds with Ni-Mhs and it is 2 years since I've been using the same Ni-MHs and I havent yet seen any sort of deterioration in the battery performance. I dont care what others say because I have experienced what is the truth about the Ni-Cds.

They almost certainly died from overcharging; a lot of phones seem to work by just continuously trickle charging the battery, which is bad for them. Whatever it was killed them though, it was not memory effect, you can be sure of that.

If you had read some battery test reports you would not have said that it is completely irrelevant. As I said that the difference may not be so obvious to us but to those people who have done battery testing the difference can be easily verified.
Battery test 1

That's a good link alright, but again it contradicts what you're saying- the chap uses Maha chargers on every brand of battery he tests, he certainly doesn't match charger and battery brands. There's absolutely no reason to do this.

penyekz

At the rate of 200mah on my charger, how long should i be charging these 2100mah aldi batteries without damaging them?

coolio_2

wheres the best place for a charger?

royalsteve

Stompa wrote:

A standard alkaline AA battery is 1.5V, whereas rechargeables are typically 1.2V, and this can mean that they won't work in some cases. I've never had much luck using rechargeables in clocks for example.

also rechargeables shouldnt be used in smoke detectors/carbon m detectors...best to use standard akaline or lithium