[CrackedHead]

^^^

While off topic (as in not an OEM battery) - one particular battery lasted us five and a half years and went thru a lot of deep discharge cycles. Actually 15+ due to frequent starting troubles during the stint when the car was running on LPG.

This was a battery for our Premier President sometime back in the 90's - It was from Willard batteries (was called "pacesetter") or something. And the car had a dynamo for charging - no alternator in a 1973 car

It was one of the first batteries that came with an "eye" thingi that shows the state of charge of the battery.

Deep discharge cycles are not the killer - improper charging after the deep discharge is.

[R2D2]

Originally Posted by vasudeva

Update on Corolla: still going after 30 months.

Vasudeva, is this the OEM battery i.e. 32AH Exide Freedom that comes fitted on all Corollas? My old Corolla's battery was replaced in 2008 it was 30-31 months old...not because it died but I sensed it was becoming weak. Starter motor turning over just a bit slower than it used to. I replaced it with a new Exide ATB 35AH battery and it made a difference when starting the engine.

Regards,

[hillram]

My 2005 Opel Corsa,which i bought fromshow room had a Exide Freedomand it lasted a whole 4 yrs.

[Raccoon]

Originally Posted by filcord

In my case I suppose I was really lucky.
After totally draining the battery, I ran the car for about 60-odd kms, and next day got the battery tested. It showed it was okay, at least that is what the Exide fellow said. And only 3 years 10 months later it started grumbling.

Nothing lucky dude... the overall life of the battery would have been reduced. The test many not reveal that... depends on how it was tested.

[santosh.s]

Originally Posted by CrackedHead

- improper charging after the deep discharge is.

Just curious, what exactly is improper charging?

I believe common Exide UPS batteries are expected to go through about 1000 deep discharges before dying, provided you don't leave it in discharged state for long. The same is not true for auto batteries.

[trrk]

Hi,

Originally Posted by zaks

My Palio Multijet is about 15months now and from the last two days it is refusing to start the first time, does it mean the battery is going out?

One or more of your glow plugs may have gone bad. Check that first.

[CrackedHead]

Originally Posted by santosh.s

Just curious, what exactly is improper charging?

I believe common Exide UPS batteries are expected to go through about 1000 deep discharges before dying, provided you don't leave it in discharged state for long. The same is not true for auto batteries.

Most automotive type battery chargers charge at a fixed voltage (bulk charge) and have little or no automatic voltage regulation capability. They are fine for a quick boost to low batteries - but the charging voltage should (optimally) be lowered as the battery gets close to being fully charged.

Charging with a higher voltage (once the battery has reached 80+% charge) causes adverse affects.

Whenever you give your battery to the friendly neighbourhood battery shop for charging after a deep discharge, its hooked up to a high voltage charger with several other batteries - to put it simply, it doesn't get the attention it deserves.

I have a charger at home and I lower the charging voltage after 5-6 hrs of charging and then let it trickle charge for another 4-5 hours. I've experienced that this keeps the battery from deteriorating after a deep discharge.

[appuchan]

My 2001 Santro's OEM battery lasted 6 years and 3 months. Got it replaced with another Exide... I drive my car everyday. That may be the reason why it lasted so long.

[santosh.s]

@CrackedHead (what a strange nickname!),
Are you pointing towards damage due to overcharging?
Doesn't leaving them in discharged state for long also deteriorate their life?

[CrackedHead]

^^^ Well.. Its not quite the same as over charging. Its about "not so optimal" charging.

The connect and forget approach when using simple transformer based battery chargers (without any voltage regulation circuit) is not the best way to charge a discharged battery.

The best way to charge a discharged car battery is to -
A) get a better battery charger (one that regulates voltage and senses when to switch to trickle charge)
OR
B) monitor the charge state of the battery and reduce the charge voltage as the battery nears full charge.

[Raccoon]

^^^ While a microprocessor equipped charger will definitely be better for recharging a battery after deep discharge, know that the life/capacity will still have reduced. Auto batts are just not designed for deep discharge. Also, its better to get the battery charged externally with a microprocessor equipped charger, rather than letting the alternator charge it in the car.

[BMW-X5]

My WagonR Lxi 2006's stock exide battery is still going strong after 3.3years and 32K kmts
Uur Baleno Lxi 2006 's stock battery is still going string after 3.5 years and 70K KMs.
Our 1999 M800's battery exide gave up after 4.5 years and 86K kmts !!

[gigy]

Battery in car is charged on constant voltage circuit. this is basic but self regulating as initially the difference in potential difference (between alternator and battery)causes more current to flow to battery. once the battery gets charged up the difference in "potential difference" reduces and hence the current reduces.
closed circuit voltage of charged battery is more than 13v(2.25v per cell) and alternator stays at14v approx. so its like 1v difference which keeps its trickle charged all time.

if you want more efficient charging the batteries have to be charged using constant current circuit but its not practical for in car use.Its best done in a battery shop. Few do that way due to requirement of better equipment.

latest once are based on pulse charging which is microprocessor controlled.

Lead acid battery should not be left in discharged state, as it will cause the sulfation to buildup and subsequent charging will not be able to reverse the process entirely and hence battery looses its life.( effective surface area for chemical reaction reduces)

[anupmathur]

Originally Posted by gigy

Lead acid battery should not be left in discharged state, as it will cause the sulfation to buildup and subsequent charging will not be able to reverse the process entirely .....

Gigy, are there any devices that can reverse the sulphation on existing batteries?
Someone is trying to sell me a product that claims to do just that!
Does this kind of thing really work?

[gigy]

Cant say about the product but as far as i have seen sulfation keeps building up slowly and weakens the battery with time although its a slow process and not 100% reverseable. but after it has managed to form in sizeable amount batteries has to be discarded. it forms a kind of insulation between the active materials. you will have to physically dismantle it to do some recovery. its not economical.

If there is such a product then its best to ask for a demo. you can get a written off battery from the local battery shop guys for testing and see if the active material comes back to life and regains its original chocolate brown color, gas freely and not heat up in the process.
After cooling a capacity test will prove the charge retention capacity. regain of 80% is considered good enough.

Another issue is that cell imbalance happens with repeat charge-discharge cycles. that cannot be corrected until a faulty cell is replaced. thats bit difficult to do with lead acid. can be done with nickel cadmium battery