NIMH Batteries

[bighnaraj]

Hi,

I am having an camera(Canon SX120IS) which support NIMH Batteries. So I was having "Camelion - Always Ready - 2100 mAh " batteries with me. I usually kept in charge while they are not in use.

One day I while I put those in my camera then after taking only 10 snaps the battery get discharged. I couldn't understand why it happened.

please let me know.
Going further I want to purchase batteries. So please suggest which batteries should i use.
Whats the difference between normal Rechargeable Batteries and NIMH Batteries.
What type of chargers should I use.

Thanks

[LigouriRd]

Assuming that your origonal batteries were Nickel-Cadmium batteries, they can have an issue with charge memory. If the NiCad batteries do not have the thier charge fully used and then are re-charged, they can develop a memory of that charge level. When you get below that level the voltage drops and it seems as if the battery has run out of charge. You can sometimes get some capacity back by completely discharging the battery (mabye with a light bulb), re-charging and repeating this a few times.

Nickel-Metal-Hydride batteries do not have this memory effect and for the most part can be charged and discharged at any state. NiMH batteries do not have the same indicators of the full charge level as NiCads do so you should use a charger that is specifically intended for NiMH cells or you could damage the cells.

In my experience these types of batteries like to be used (I used to competitively race radio control battery powered cars). If you are discharging and recharging on a weekly basis you can see thousands of cycles. When the battery doesn't get used for a while the residual charge drops off and so does the capacity. If it is a long while the battery will appear dead. You may have to cycle it a few times to get it working again. Eventually all batteries develop crystal growth within the cell which decreases the capacity and will ultimately short the cell. It is unknown how long it takes for this to happen, but it has been my experience that lack of use makes it happen faster.

The above does not apply to Lithium-polymer (LiPo) batteries. They have a finite number of charges and discharge cycles but don't care at what charge level you charge them at. Once they no longer hold a charge there is nothing much that you can do to bring them back.

My $.02

[sk66]

Originally Posted by bighnaraj

Hi,
I usually kept in charge while they are not in use.

Overcharging NiCad batteries will ruin them.

[bighnaraj]

Originally Posted by sk66

Overcharging NiCad batteries will ruin them.

Thanks for your suggestion, but can u tell me is there any chargers in market which get auto off feature if batteries charge. if yes, then please let me know the make.

[bighnaraj]

Originally Posted by LigouriRd.

Nickel-Metal-Hydride batteries do not have this memory effect and for the most part can be charged and discharged at any state. NiMH batteries do not have the same indicators of the full charge level as NiCads do so you should use a charger that is specifically intended for NiMH cells or you could damage the cells.
My $.02

can u suggest any make of these type of chargers.

[sk66]

Originally Posted by bighnaraj

Thanks for your suggestion, but can u tell me is there any chargers in market which get auto off feature if batteries charge. if yes, then please let me know the make.

Yep, but they aren't cheap
http://www.kirkphoto.com/Maha_PowerEX_Charger.html

[mipo]

One more vote for Maha chargers & Powerex Battery.
Now using the new Imedion's 2400mha

[LigouriRd]

You know it just dawned on me that your Camelion "always ready" batteries are not really rechargable batteries at all. They are most likely alkaline batteries, kinda like those rayovac renewal batteries. They can be recharged but there is a very limited number of times you can do that before they give out.

Originally Posted by bighnaraj

can u suggest any make of these type of chargers.

You could try the camelion chargers they list thier ability to charge both NiCads and NiMH's. There are tons of chargers out there, just make sure it says it can safely charge NiMH's.

[jdepould]

Just my $0.02:

Sanyo Eneloops are the best standard-size (AA, AAA) rechargeables I've ever used. I started using them in my flash, now I use them everywhere I can--especially the Wii. You can get them on Amazon pretty cheap.