[Vid6639]

what rks has mentioned is absolutely true and the same was informed by the lancer service guys.
My battery died down twice and both times I had to call the service centre to jump start the car. Paid 400 bucks on both occasions.
They say MPFI cars should not be push started due to damage to cat con as well as sensors.
Finally one day I had no choice but to push start at late night.
This should be avoided.

1. A battery works like a capacitor, much like a capacitor works like a battery. Which means it also smoothens out the dirty spiky ac voltage generated by the alternator. ALTERNATor generates AC which is smoothed out by a rectifier and converts it to DC to charge your battery.

2. The electrical systems are designed to generate higher voltages than the designated battery (So that it may charge)
When there is a battery, even if it is a dud battery, it keeps the voltage in check. Without one, the electrical systems can go haywire.

Sam very good description. Are you an electrical Engineer?

[Bass&Trouble]

Originally Posted by rks

Regarding battery life, it will be dependent on the total number of charge-discharge cycles. So heavy usage of ICE will bring down the battery life. But it is not as simple as this. My laptop guide advises that if the battery is not frequently used, then at least once a month it should be brought to a state of near-total discharge (less than 3% charge left) and then charged again. I think this applies to car batteries as well. Over-charging is bad for battery health.

Standard lead acid batteries work differently from the batteries of Laptops etc. Fully discharging your car battery will not prolong its life. Unless it's a dry cell, similar to laptop battery, like the kind made by Stinger.

[rks]

Originally Posted by Bass&Trouble

Standard lead acid batteries work differently from the batteries of Laptops etc. Fully discharging your car battery will not prolong its life. Unless it's a dry cell, similar to laptop battery, like the kind made by Stinger.

Actually the laptop battery is Lithium-Ion, not Lead-Acid. What the procedure of dicharge-charge (called "reconditioning" the battery) does is to make the battery recover its full charge capacity. It has something to do with the "memory" of the battery -- if you don't use the battery to full extent, it somehow "remembers" that and next time you charge it, the charge capacity comes down.

Edit: An internet search proves you right, B&T. It seems lead-acid batteries do not suffer from the "memory effect", which is highly controversial in any case. So one should not discharge the car battery unnecessarily.

[Sam Kapasi]

A simple query has turned into a superlative electrical discussion. My compliments gentlemen.

[sixthsense]

This is what the swift manual has:

CAUTION : Your vehicle should not be started by pushing or towing. This starting method could result in permanent damage to the catalytic converter. Use jump leads to start a vehicle with a weak or flat battery.

[theEnd]

I dont see why everyone is so eager to start their cars and then throw the battery out.

Maybe the performance mod guys want to lower the weight of the car. Perhaps use the empty space to throw in a turbo or some NOS tanks.

The ICE guys must be thinking.. nice place to tuck away a really big mono amp for the 15" sub in the boot! Or even better stick a sub in the engine bay!

[hydrashok]

Originally Posted by theEnd

Or even better stick a sub in the engine bay!

That would be great for upfront bass!

[esteem_lover]

Originally Posted by theEnd

I dont see why everyone is so eager to start their cars and then throw the battery out.

Maybe the performance mod guys want to lower the weight of the car. Perhaps use the empty space to throw in a turbo or some NOS tanks.

The ICE guys must be thinking.. nice place to tuck away a really big mono amp for the 15" sub in the boot! Or even better stick a sub in the engine bay!

thank you theEnd... at last, there is a whiff of fresh air in a dark stale room.

you guys & your fears had me so nervous last night when i had my ICE running for a while, that i had to keep a couple of guys in the vicinity, just in case. i have been using my ICE to watch movies for elongated periods of time & so far so good. dont put the fear in me now, ok ???

[mithun]

Originally Posted by Sam Kapasi

Well, I used to have a Yamaha RX100 when I was younger. And Never really needed the battery and it was pretty much dead. (It was a 6V battery anyways)

So one day, I threw away the battery. Everything worked fine, but I kept losing bulbs. Made no sense to me initially till I realised 2 important things

1. A battery works like a capacitor, much like a capacitor works like a battery. Which means it also smoothens out the dirty spiky ac voltage generated by the alternator. ALTERNATor generates AC which is smoothed out by a rectifier and converts it to DC to charge your battery.

2. The electrical systems are designed to generate higher voltages than the designated battery (So that it may charge)
When there is a battery, even if it is a dud battery, it keeps the voltage in check. Without one, the electrical systems can go haywire.

Sort of what B&T said.

I strongly disagree with you in the case of bikes.

My 12 year old Bajaj bike(now sold off) ran for about 6 years without any battery. My mechanic disconnected all the indicators, horns etc from the battery setup and made it to work directly from the AC produced by the bike's dynamo. And there was no problem of bulbs gone kaput or electrical system gone awry. And all the bulbs are still the OEM ones.

The only downsides were the horn/indicators never worked in the neutral and the power output was pretty low for horn/indicators to work in the night !!!

[Bass&Trouble]

Originally Posted by mithun

I strongly disagree with you in the case of bikes.

My 12 year old Bajaj bike(now sold off) ran for about 6 years without any battery. My mechanic disconnected all the indicators, horns etc from the battery setup and made it to work directly from the AC produced by the bike's dynamo. And there was no problem of bulbs gone kaput or electrical system gone awry. And all the bulbs are still the OEM ones.

The only downsides were the horn/indicators never worked in the neutral and the power output was pretty low for horn/indicators to work in the night !!!

Arre baba. You cannot run any vehicle's electricals off AC!

What Sam meant is that, older vehicles had dynamos. A dynamo is something that produces DC power when it is operating. This is used to charge the battery and supply to electrical loads directly. All newer vehicles have alternators. These produce AC, and need to be rectified to DC before charging the battery. Your bike surely has a dynamo. Thats why, the charge produced when the bike is moving is powering your spark plugs and other electricals.

[navin]

Originally Posted by Bass&Trouble

What Sam meant is that, older vehicles had dynamos. A dynamo is something that produces DC power when it is operating..

The primary difference between an alternator and a dynamo is what spins and what is fixed. On a dynamo windings of wire (the armature) spin inside a fixed magnetic field. On an alternator, a magnetic field is spun inside of windings of wire called a stator to generate the electricity, hence one can use larger wire in an alternator and carry more current.

In an dynamo the armature generates AC and to convert the current to DC so it can charge your battery and run your headlights, a device called a commutator is used, an alternator on the other hand uses a diode bridge.

End of EE 101.

[santosh.s]

Originally Posted by Bass&Trouble

Standard lead acid batteries work differently from the batteries of Laptops etc. Fully discharging your car battery will not prolong its life. Unless it's a dry cell, similar to laptop battery, like the kind made by Stinger.

In fact discharging is bad for lead-acid type of batteries because it can damage the battery and reduce its life. Thats why it is recommended by manufacturers to keep it as much charged as possible. Also, charging them at faster than normal rate (using higher currents) is bad too.

One should never apply recommendations of one battery type to another as each one of them utilize a completely different chemistry.

[rks]

Originally Posted by santosh.s

In fact discharging is bad for lead-acid type of batteries because it can damage the battery and reduce its life.

I agree that *complete* dicharge is probably bad for the battery. But many old-timers still insist that occasionally discharging (but not fully) and then recharging the car battery is good for its charge-holding capacity. I have read on the internet though, that a lot of this is just myth. Lead-acid batteries apparently do not suffer from the memory effect as I mentioned earlier. So it is probably true that the car battery should always be kept fully charged.

For my laptop the manufacturer recommends re-conditioning the battery once a month if the battery is not frequently used, i.e., reduce the charge to less than 3% and then re-charging to 100%. Occasionally the battery has to be "deep-cycled", as per the manual, i.e., the charge reduced to 0% and then increased -- this can be automatically done by choosing "Re-condition the battery" on my laptop. But the lapop battery is Lithium-Ion, which as per many internet sources, also does not suffer from the memory effect. The memory effect seems to apply predominantly to Nickel-Cadmium cells as per these sources.

So it is not clear to me why the manufacturer recommends this procedure. But on one occasion, I accidently kept my laptop in the stand-by mode all night without connecting to power and in the morning the computer had shut down with charge at 0%. I re-charged the battery and found that the charge capacity increasded from 31 Wh to 39 Wh! This much increase never happens even when I choose "Re-condition" on my laptop (I get atmost 1 Wh).

[santosh.s]

rks, as per my knowledge also (and beliefs!) reconditioning is required for NiCd batteries, not for lithium-ion. What I doubt is that reconditioning is recommended probably to re-calibrate battery measurement circuit in the laptop. That in turn implies that you might have seen an improvement in just the reading, not actual capacity of the battery... not too sure .

[rks]

Originally Posted by santosh.s

rks, as per my knowledge also (and beliefs!) reconditioning is required for NiCd batteries, not for lithium-ion. What I doubt is that reconditioning is recommended probably to re-calibrate battery measurement circuit in the laptop. That in turn implies that you might have seen an improvement in just the reading, not actual capacity of the battery... not too sure .

As per the manual (this is a SONY battery fitted to an IBM laptop) the reconditioning is supposed to improve the charge capacity of the battery. The design charge capacity was 47.52 Wh, and now it has dropped to about 33 Wh after almost 2 years. Which is very good, for the manual says that after 1 year under normal usage the charge capacity should drop to 70% of the design value. I never use the battery, so I recondition approximately every month.

What you say about the improvement being merely the reading may well be true. Because after the charge capacity reading jumped up to 39 Wh (after the unintended zero charge/recharge cycle noted in my previous post) the next time I reconditioned by the normal procedure, the reading again dropped to 33.5 Wh.