How to know if your battery needs changing?

[Panda]

Hi everyone,

 

Dunno if this question has been asked before, but is there a sure way to tell whether it is time for a battery change before the battery completely fails on you?

 

Measure with voltmeter across the terminals?

[Turbobrick]

Voltmeter across terminal on a cold battery (overnight rested), should read >11.5V. Once it touches low 11s or 10+ time to shop for a new batt to be safe.

 

Or when the car is slow to crank, then immediately get a new one!

[Andrewkb]

Since we're at this .. wonder if "dead" battery can be re-charged/re-vitalised?

 

I don't think those dead battery are thrown away right ?

[Panda]

Thanks TB! So I'll just get me standard multimeter to do the test. seems pretty straightfoward.

[Panda]

Hi Andrew,

 

I think Vtim posted something in the HVS thread regarding deep cycle battery.

http://www.mycarforum.com/forum/gforum.cgi...t=324425#324425

 

Following the link to howstuffworks website regarding deep cycle batteries at http://auto.howstuffworks.com/question219.htm I have learnt that standard car batteries once totally discharged, its a very bad thing as it is permanently damaged.

 

Deep cycle batteries can be recharged though...

 

As for being thrown away... not sure... re-con battery? Hmm...

[Turbobrick]

Depends on "dead" are the batteries.

 

I had my T-bird battery die on me once, went to an autoparts shop and they charged in FOC within an hour

 

Sometimes the battery just got drained and needs a recharge, a battery is truely dead if it doesn't hold charge

[Vtim]

The Lead Acid Accumulator (or Battery) have Sulphuric Acid inside so cannot any how throw away

 

It depends on the how 'dead' is 'dead', it could be the battery are almost completely drain, or the acidity level is low, or not enought distill (battery) water.. These type still can be revive

 

Once the plates inside it have start to bend (buckle) & sometimes touches the adjacent plates, most likely the battery is dead (SC) & cannot be recharged or jump start Encounter this case when I try to jump start my friends car & found out the battery have Short-Circuited as the plates have buckle & touches the adjacent plates

[Mondeo]

I saw there's a battery alarm to inform you whether the battery going to 'die'. Or buy a voltmeter just plug on lighter switch will know.

[Panda]

 

I still have my trusty digital multimeter with me! Tested cold 12.62V.

 

Yay! No need to change battery yet! 2 years 3 month old standard battery, still okay! Save money...

[Panda]

Tested 12.62 cold.

 

Too bad! No excuses to change to a nice maintenance free battery yet! Eyeing for a Delphi.

 

 

Thanks!

[Saaber]

or a Varta...

[Rizzzl]

I check the battery voltage using RSM. Good condition battery tested cold 12.5v and 13.8 while driving. However, I experienced battery about to be goner when I heard that it sounded weak during cranking one morning. The voltmeter tested cold showed 12.3v and after that 13.8v while driving right? SO it should be OK right? WRONG - after driving for about an hour or so at 13.8v, it failed to restart again. Needed to jump start. So are voltmeters good indicators? To me it helps showing that battery is charging when driving i.e. alternator working but when the battery is about 2 years old, start relying on your ears.

 

BTW, when the cranking sounds weak, it could be the last few hours of your battery - meaning the next time you start the car - it might not crank.

[Panda]

Yo Rizzl, haven't seen you around for such a long while!

 

According to what you say, I better be more alert! Afterall the battery is more than 2 years old I believe. Cranking still looks pretty good, up till now that is. I think... I hope...

[Panda]

Wahahaha~! Yeah! Varta!

 

Now the excuse to change battery is reborn...

[Guyver]

  Quote

Hi everyone,

 

Dunno if this question has been asked before, but is there a sure way to tell whether it is time for a battery change before the battery completely fails on you?

 

Measure with voltmeter across the terminals?

 

Think as long as your battery is ok... car can start... and u do regular maintenance... your battery doesn't needs to be externally charged... unless.. your battery is old liao....