Typical life span of AA NiMH batteries?

Morning PT.  I was just cleaning out my desk as I have  a new one getting delivered tomorrow. I found 7  old AA NiMH batteries.  I need to dig up my charger for this, however I seem to recall it has a function to discharge.  Honestly I have no clue where the charger is.  

But will these batteries that have got to be 8 years old hold a charge?

NiMH was the fist try to replace the banned NiCad electro-
chemical compound. NiMH had a longer shelf life but eight
years is a bit stretched if I remember well.

After all the time, the cells might have discharge well over
eventual recharge and possible polarity switch. Let them be.

I would suggest to replace them with Black Eneloop Pro cells
that are of stupendous quality, pretty cheap and use a power-
ful pulse charger.

2,5 A Black Eneloop Pro cells

I have recharables that I've had for nearly 6 years and they still work and hold a charge.  I don't think the charge is as strong, but hey they still work.  

G'day Roy+ team

I have used NiCad batteries since the 1960s and NiMh since the 1980s
Recently the last of 4-original "AA" NiMh batteries from Radio Shack, bought with their charger in 1986 finally died - used constantly over 30 years in a small torch that used 4-AA batteries, and recharged regularly over the years

Roy - to answer your main Q ... will (your) batteries still hold their charge ... 'no' mate - after 18 months of non-use, just about all rechargeables will have faded

I would suggest that you find a good AA recharger, one that has some 'smarts' to regulate the charge rate and give the old batteries a try. As said above, the 'Eneloop' batteries probably have the best reputation these days (with Ever-ready Energizers the poorest reputation) and it is quite likely that you can pick up a charger + 4-AA batteries at the same time & for a reasonable price

Hope this helps
Phil from the great land Downunder
www.flickr.com/photos/ozzie_traveller/sets/

ShutterPal wrote: I have recharables that I've had for nearly 6 years and they still work and hold a charge.  I don't think the charge is as strong, but hey they still work.  

Yes, me too but ours have been active all that time.
Dormancy is the worst for built in electro-chemical
compounds — it is all depending on the inner resis-
tance, but they will all get there.

ADDENDUM

The deterioration is affecting the isolators in the cells too.

Ozzie_Traveller wrote: G'day Roy+ team

I have used NiCad batteries since the 1960s and NiMh since the 1980s
Recently the last of 4-original "AA" NiMh batteries from Radio Shack, bought with their charger in 1986 finally died - used constantly over 30 years in a small torch that used 4-AA batteries, and recharged regularly over the years

Roy - to answer your main Q ... will (your) batteries still hold their charge ... 'no' mate - after 18 months of non-use, just about all rechargeables will have faded

I would suggest that you find a good AA recharger, one that has some 'smarts' to regulate the charge rate and give the old batteries a try. As said above, the 'Eneloop' batteries probably have the best reputation these days (with Ever-ready Energizers the poorest reputation) and it is quite likely that you can pick up a charger + 4-AA batteries at the same time & for a reasonable price

Hope this helps
Phil from the great land Downunder
www.flickr.com/photos/ozzie_traveller/sets/

What's funny is I originally read your message and thought you had batteries from the 1960s that you were still using today!  ha ha ha

Tristan R wrote: What's funny is I originally read your message and thought you had batteries from the 1960s that you were still using today!  ha ha ha

My NiCads were both wet-cell units as used in the Mecablitz flashguns with their over-the-shoulder carry power packs - then "D" size batteries for various portable items ....

For reference purposes ... NiCad batteries are still in widespread use today ~ for example, all your electric toothbrushes / razors that sit on a docking station -and have sealed bases that you cannot get inside - all have NiCad batteries

Hope this helps
Phi

Ozzie_Traveller wrote: My NiCads were both wet-cell units as used in the flashguns....

The NiCad electro-chemical compound (nickel oxide hydroxide
and metallic cadmium as electrodes) has the lowest inner resis-
tance of all (best for flash and power tools!), and that means the
shortest shelf life and the most dangerous cell to shunt.

It can be charged at up to 20Cs and memory-effect is specific
to sintered nickel-cadmium cells.

Speaking of rechargeable batteries, when you store your batteries, are you storing them at a full charge?  If so, how often will you charge them when not in use? 

Chris Briggs wrote: Speaking of rechargeable batteries, when you store your batteries, are you storing them at a full charge?  If so, how often will you charge them when not in use? 

Hi Chris,

the relative self life of any electro-chemical compound is directly
linked to its inner resistance— NiCad: +/- 60~90 days, NiMH: 9 m.

Cells should not reach down lower than 15 % of the full charge. A
good — though approximate — way to read the cell is to read the
residual voltage. A 1.5 V cell should be recharged when reading in
the area of +/- 0.9 V with a VOM.

4 years and going strong with mine

The reward to keeping them active, Carry!

Mine are 26 months old and still going strong, not as long as others, but working well for me.