why are batteries supposed to be charged all the way the first time?

[dpopiz]

it seems like whenever I get some new thing with a built-in rechargeable battery, I rip it out of the box and plug it in to charge for a few mins and then try it out, and then I open the manual and see a big warning that says I should charge it for a few hours before using it the first time?

why is that?
am I permanently damaging something by doing so?

 

[Eli]

Yes, you should let the batteries charge fully before beginning the charge/discharge cycles.

Everything you ever wanted to know about rechargable batteries, and more

 

[GtPrOjEcTX]

they're nicad or nimh which loose charge for just sitting there doing nothing. so by the time you get the product, the batteries are just about dead anyways and should be charged full. whether it hurts something or not to use it when partially charged, I don't know.

 

[vi edit]

Some batteries have a "memory" of sorts that remembers what the first charge was and then will only charge up to that point in future charges.

This was a big thing in older cell phone batteries. I don't remember the specific types.

 

[Kaervak]

Originally posted by: vi_edit
Some batteries have a "memory" of sorts that remembers what the first charge was and then will only charge up to that point in future charges.

This was a big thing in older cell phone batteries. I don't remember the specific types.

NiCad batters are the ones with the memories. Lithium Ion ones don't have a memory and can be charged at any time without screwing things up.

 

[dpopiz]

well, all the battery powered things I use that have that warning are li-ion and I thought li-ion doesn't suffer from memory effects

 

[Eli]

Originally posted by: GtPrOjEcTX
they're nicad or nimh which loose charge for just sitting there doing nothing. so by the time you get the product, the batteries are just about dead anyways and should be charged full. whether it hurts something or not to use it when partially charged, I don't know.

In general, the deeper you cycle a rechargable battery(read: the deader it gets), the more damage is done.

By the same token, leaving them on the charger for long periods of time can damage them, too.

Read that link I posted. It's good stuff.

Rechargable batteries actually require quite a bit of maintenance. It is easiest on the battery to charge them when they're at around 50% charge, but you also must fully discharge/recharge the battery say, once a month as prevantitive maintenance.

Originally posted by: dpopiz
well, all the battery powered things I use that have that warning are li-ion and I thought li-ion doesn't suffer from memory effects

I don't believe they do.

NiCD and to a lesser extent, NiMH do though. That's what the full discharge/charge cycle is for. The memory effect is caused by crystalline formations within the battery. Charge/discharge cycles help reconstitute the crystals.

There are chargers that do this for you.


<--- has been doing a lot of battery research.