Can a car battery sit uncharged for two years?

[speeder]

And still be OK? If not, why? TIA.

[HardDrive]

In my experience no, but I don't know why.

[Tishabet]

Ditto HD's experience. I've had Optimas go bad after 1 year discharged.

[pwd72s]

In the old lead acid with filler caps days a battery would sit on the shelf "dry". The acid would be added at the time of purchase.

We can't do that with today's sealed batteries. My theory is that is why some are seeing optimas fail prematurely.

[widebody911]

Depends on the battery. I have several cars that I don't drive very often. One has an older Optima that's about 12 years that's still viable; I have another Optima that's maybe 5 years and is dead as a doornail. I've had 6v lead-acid crap out in 6-8 months of non-user.

To answer your original question, yes, it will eventually go bad, but how fast it does is a function of battery age, quality, temperature, etc.

[Andy O'solo]

I too have an Optima battery in the garage. Its been on a trickle charger for over a year but not used ... pending car's restoration.

My questions are, how can I determine if this battery is even worth continuing with the trickle charge? Am I wasting my time & electricity? Is it dead of alive?
What type of testing meter/process can determine its usability?

Thx.

[fastfredracing]

I consider myself lucky when they survive winter storage here.

[pwd72s]

Originally Posted by Andy O'solo

I too have an Optima battery in the garage. Its been on a trickle charger for over a year but not used ... pending car's restoration.

My questions are, how can I determine if this battery is even worth continuing with the trickle charge? Am I wasting my time & electricity? Is it dead of alive?
What type of testing meter/process can determine its usability?

Thx.

Do you have a multimeter? If it's at 13 volts or so, should work. BTW, not all trickle chargers are the same. I recently switched from an old school battery tender plus to one of these linked below. This one has a "bad battery" light if the battery won't hold a charge. After 4 years the original battery on my '09 Mustang caused this light to glow. I'm now running an optima #35 red top.
Xtreme Charge XC100-P PulseTech Charger (100X010)

Really a pretty cool charger/maintainer with a pulse technology that cleans sulpates from the plates...read about it in the link above.

Optima now sells a charger/maintainer for $200 that sounds really nice as well.

[red-beard]

3% to 5% per month. It would be best to recharge every few months. Try recharging it and see.

[KFC911]

Originally Posted by pwd72s

....I'm now running an optima #35 red top.
Xtreme Charge XC100-P PulseTech Charger (100X010)

That's what I have on the Optima red top in the 911. That said, I've got 3 Optima blue tops on my bass boat, and they all have "Battery Tenders" on them that work just fine too. My oldest blue top is 13 years old (and actually sat mostly discharged) for a couple of years (6-7 years ago), I figured it was shot until I charged it up...been just fine ever since (note: blue top is a deep cycle designed to be discharged...different than a red top). In an ideal world, never let your car batteries discharge...no bueno imo.

[sammyg2]

If a conventional lead acid battery goes dead, the plates can sulfide up and lose their battery-ness.
they get coated with a sulfur compound and won't conduct no mo. Either that or they short together, can't remember.


Sometimes you can rejuvenate an old battery by replacing the acid with new stuff.
I had a buddy who swore he could bring an old dead battery back to life simply by banging in on the floor. I saw him do it once and it worked, wouldn't take a charge before but would afterward.

I don't recommend that tho ... keeping it charged is the best way to keep it alive.

[BeyGon]

can you park your Volt for a year and expect it to still work, serious, I don't know. How long are they good for in storage.

[ossiblue]

Sammyg2 has nailed it. Batteries that sit without full recharges will build up dense formations of sulfide crystals that cannot be removed. These crystalline coats prevent ion transfer and also recharging if allowed to develop over many months. Long storage of lead-acid batteries requires regular full charging to prevent this from happening. Your two year dormant battery may still take and hold a charge, but it is not long for this world.

[ossiblue]

Originally Posted by BeyGon

can you park your Volt for a year and expect it to still work, serious, I don't know. How long are they good for in storage.

That's a good question. I think, however, the Volt and most other modern electrics use a lithium-ion battery instead of the lead-acid, in which case the problem of long periods of non-use may not be the same.

[mreid]

Batteries do have a very high resistance internally. Any resistance with voltage applied generates current flow (ohm's law I=E/R). Even this tiny trickle current is enough to drain the battery. It is also enough to damage it. A trickle charger is your best defense.

[KFC911]

Originally Posted by mreid

Batteries do have a very high resistance internally. Any resistance with voltage applied generates current flow (ohm's law I=E/R). Even this tiny trickle current is enough to drain the battery. It is also enough to damage it. A trickle charger is your best defense.

I learned this the hard way on my bass boat (even though I recharged the batteries after each outing) many years ago.

Optimas + trickle =

[vash]

So. Do AAA batteries stored in the fridge fair better than those stored at room temp?

[Ronbo]

Originally Posted by BeyGon

can you park your Volt for a year and expect it to still work, serious, I don't know. How long are they good for in storage.

Wouldn't it work using the gas engine even if the battery were fully depleted?

[rick-l]

I think if you let a Li-Ion battery completely discharge it will not accept a charge.

I also think Boeing is about to become the industry experts on failure modes of Li-Ion batteries.

[wdfifteen]

Thank you. This thread motivated me to go out to the shop to check on the 911. The battery was completely discharged - so flat it wouldn't take a charge at first. If it had gotten really cold here it could have frozen and cracked the case. Thanks again.