How to know battery going to be flat?

[Mcf777]

Aliexpress below SGD100.

If SOH is State of Health,   the % may give an indication of the health of the battery.

Alternatively,  the A and internal resistance may also give an indication but reference needs to be taken when the battery is new or known to be good.   

E.g.  if SOH is at 50%,  you have to decide if want to change.  Likely I may wait until 25%.  

 

Just curious, the sidewalls of the old battery got become bloated? 

Dont have. the old battery exterior still look swee swee.

[Kklee]

Dont have. the old battery exterior still look swee swee.

 

It is the battery connector on the battery that broke right ?

I suspect the previous battery got a very hardy casing. 

[Kb27]

Yesterday, my car have weak cranking.

Immediately drove to battery shop and change it.

Amaron battery, lasted me for two years.

 

the battery connector broke into half and full of greenish powder on it. Lucky no short circuit.

 

Changed the same brand 80ah. I think called hi life pro.

S$160 for the battery.

 

The battery terminal (correct terminology), is corroded by acidic gas emanating from cracks in the battery post.

It reacts with the terminal and leave behind greenish copper salt.

The terminal is weakened by the loss of metal and finally it will break.

 

If you have changed the terminal, to minimize corrosion, apply some high temp grease on the terminal to protect it from the acidic gas.

[Mcf777]

The battery terminal (correct terminology), is corroded by acidic gas emanating from cracks in the battery post.

It reacts with the terminal and leave behind greenish copper salt.

The terminal is weakened by the loss of metal and finally it will break.

 

If you have changed the terminal, to minimize corrosion, apply some high temp grease on the terminal to protect it from the acidic gas.

Thks for the info.

Cost S$10 to change the Battery terminal. i saw them applying grease and also spray something onto it .

[Spidey10]

Not just BMW, all cars need power to start.

Voltage like 12.1V is just the state of charge of the battery.

So any battery that is charged have a voltage ranging from 12.1 (low charged) to 12.7V (fully charged)

Power to start requires current.

Current to start may be anywhere from 150A to 200A and the battery must be able to provide it.

It can't provide that current when it's discharged (below 12V), like those who put dashcam and discharged it overnight.

 

If you have a bad battery, it can still read 12.6V, but fail to crank the engine.

 

You can have a small lithium jump starting battery or a good 35AH battery and still start a BMW.

There's nothing special.

 

Actually the battery is just for turning over the engine.

Starting the engine requires, compression, petrol and air, which is not the function of the battery.

 

So, the answer is even putting a small 35AH battery on a BMW will work, to start its engine.

for BMW, does the dash light up if the batt is due for a change?

[Kb27]

for BMW, does the dash light up if the batt is due for a change?

 

That I dunno. It depends on the model I guess, and some may more advanced features.

 

For normal cars, there's a battery sign on the dashboard.

 

When you turn on (without starting the engine), the sign comes on. It indicates it's normal, the bulb is working.

But it doesn't tell you the condition of the battery.

 

When you start your engine, the alternator runs, if the battery is good,

Now it's voltage is higher than the battery, the sign goes off. It indicates the charging system is ok, which means the alternator is ok.

 

When the engine is running, if the battery sign comes back on. It means there's a charging problem, it's not a battery problem.

 

For any car that is capable of indicating a change of battery, it must have some sort of algorithm to either check voltage or CCA.

Not just simple off engine battery voltage check, but something like crank voltage. What's the lowest voltage the battery goes down to during cranking, or how fast the recovery of battery voltage ?

 

Battery tester use algorithm to check CCA and allows you to make a decision on when to change the battery.

However, it requires you to input a factory spec CCA reading first, before it can make a recommendation, since not all batteries are the same size or have similar CCA.

[inlinesix]

for BMW, does the dash light up if the batt is due for a change?

 

By the time you see error message, it is too late liao.

 

If battery in the boot (& engine bay), it usually last 5 years (provided you have 1 long drive every month to charge the battery).

 

It is a good practise to check condition of battery from Year 2 of battery onwards.

[Spidey10]

That I dunno. It depends on the model I guess, and some may more advanced features.

 

For normal cars, there's a battery sign on the dashboard.

 

When you turn on (without starting the engine), the sign comes on. It indicates it's normal, the bulb is working.

But it doesn't tell you the condition of the battery.

 

When you start your engine, the alternator runs, if the battery is good,

Now it's voltage is higher than the battery, the sign goes off. It indicates the charging system is ok, which means the alternator is ok.

 

When the engine is running, if the battery sign comes back on. It means there's a charging problem, it's not a battery problem.

 

For any car that is capable of indicating a change of battery, it must have some sort of algorithm to either check voltage or CCA.

Not just simple off engine battery voltage check, but something like crank voltage. What's the lowest voltage the battery goes down to during cranking, or how fast the recovery of battery voltage ?

 

Battery tester use algorithm to check CCA and allows you to make a decision on when to change the battery.

However, it requires you to input a factory spec CCA reading first, before it can make a recommendation, since not all batteries are the same size or have similar CCA.

So meaning there is no preemptive message to inform you that the batt is Low...

By the time you see error message, it is too late liao.

 

If battery in the boot (& engine bay), it usually last 5 years (provided you have 1 long drive every month to charge the battery).

 

It is a good practise to check condition of battery from Year 2 of battery onwards.

Thanks bro

[Axela525]

[Kb27]

So meaning there is no preemptive message to inform you that the batt is Low...

 

 

In most cases, no.

 

The best thing to do is to get the battery checked periodically.

CCA check is 90% reliable and will give good indication of whether to change the battery or not.

 

BMW battery tend to last longer, bcuz it's placed at the back where there is less heat, unlike most cars where the battery is placed in the hot engine compartment.

 

Heat kills battery.

 

[stellapike]

There are some warning signs through which we can identify that our car battery is dead or dying:

Your engine cranks but doesn't start.
No crank, no start, no lights!
Cold cranking is hard work.
You've jumped it a lot already.

It’s been my personal experience as last year I faced similar problem with my car battery and then Swift Battery Helped me to fix it with change new car battery.

Edited October 13, 2017 by stellapike

[Fern0324]

usually takes longer to start car.. especially after parked on cold raining day.

 

Usually my technician will write the date changed on my battery and I have it changed within 2 years (after once stranded in orchard road with car can’t start .... ) and no more problems since

[Hockann]

Yes, on cold days, engines need more warm up. On a hot sunny day, the engine is already warm.

[Ahzq17]

You can get the battery tested every time you go to do your regular wheel rotation/balancing or car servicing.  The workshops has the equipment to test your car battery and advise you from there.

 

It's wet weather now.  The old batteries in the car will start to fail faster because of contraction in the early morning due to the cold weather.

 

Get it replaced cheaply before you need outside service help, which is more expensive due to the additional service charges.

 

There's actually a free trial now.  can sign up if your battery is towards it's end of life -  https://goo.gl/Sp9LFg

[Mcf777]

 

Bro,

 

How to prevent battery from dying?

I didnt drive for 10days. Nearly couldnt start the car today.  Whole car like vibrating for about 10-15secs

 

80mah Amaron battery less than 1.5mths old.  

Park at MSCP (under shelter)

Took out all mobile phone adapters and in-car camera plug

 

Previously, im using 65mah or 70mah (cant remember) Amaron battery

and I dont have such issue when i leave the car for almost 2 weeks.

 

Next month going two weeks holidays. must get prepare for the worst.

Thks

[Kb27]

Bro,

 

How to prevent battery from dying?

I didnt drive for 10days. Nearly couldnt start the car today.  Whole car like vibrating for about 10-15secs

 

80mah Amaron battery less than 1.5mths old.  

Park at MSCP (under shelter)

Took out all mobile phone adapters and in-car camera plug

 

Previously, im using 65mah or 70mah (cant remember) Amaron battery

and I dont have such issue when i leave the car for almost 2 weeks.

 

Next month going two weeks holidays. must get prepare for the worst.

Thks

 

Need to check the battery. Most likely, it's drained or the electrolyte is weak.

If that's the case, need to re-cond by special charging.

You can contact me further by pm or call me.

 

[Dario212]

Hi all ,

How do you know that battery going to be flat ?

When the car starts , it prompt you "switch to economy mode " . Can this be 1 of the symptoms that battery is weak too ?

 

Cranking sound . Usually it took me 1 crank to start the engine . But yesterday the cranking sound is long before engine start , can this also telling you that battery going to be flat soon ?

Pls advise

http://www.ebay.com/bhp/battery-gauge

[Jamesc]

Just ask my MIL.

 

When it goes flat she will tell you.

 

I knew it was going to happen.