Can my car battery recharge or a new one???

what7

My 2009 Corsa diesel car battery has refuse to turn on this morning.
Tried to jump start, no joy.
Roadside breakdown came, ran some test
BATTERY TEST 
REPLACE BATTERY
SOC: 00%
VOLTAGE : 9.40V
SOH : 0%
MEASURED : 45A
SELECT INPUT : EN
RATED: 640A
INTERNAL R : 56.61MM
Eventually got it running, and recommend to get a new battery, which I will likely to follow, but I just want to check with this forum , making sure it cannot be recharge.

Grumpy_chap

When did you last use your car?

If you have a battery charger, simply charge overnight and if the problem is solved, happy days.

what7

I didn't use my car for 5 weeks in March and it was fine.
Has been using it in since April until this month.
Left it unused for 2 weeks and now

Grumpy_chap

Maybe the reduced use has taken its toll.  Try charging as you can't lose anything.  If that doesn't work, buy a new battery from Halfords.

what7

Good idea
does the test show anything worth reading into? Obviously can't go worse than 0%  
I read online that 9.40V in a 12V battery is quite bad.
Will recharging bring the 9.40V back to 12V?
What should a average battery test show?

shaun_from_Africa

what7 said:

I read online that 9.40V in a 12V battery is quite bad.
Will recharging bring the 9.40V back to 12V?

Allowing a lead acid battery to drop below about 10.5 volts (for a 12v battery) will cause some permanent damage but how severe this will be is impossible to tell straight away.
If it does recharge okay, the overall capacity will still be reduced as will the maximum current that the battery can deliver but this doesn't automatically mean that the battery will need replacing now.

Depending on the size of the battery and the actual power needed to start your car, the reduced capacity may not be too important especially if you are using the motor on a regular basis.
However, if it's left idle for a while and especially when the weather starts getting colder, you may well find that one day you get stranded with a dead battery.

AdrianC

It will recharge. But... the battery will have been internally damaged. Its life has been shortened.

How old is it?

what7

I had the car from new, I cannot seem to remember changing the battery once, nor can I find any documentation for it.
Is it unreasonable to think I had the battery for 11 yrs , and 75k mile on it.

cymruchris

If it is indeed 11 years old, you’ve done quite well. It’ll definitely be worth changing. If you’re going to get someone to do it for you, get them to check the voltage when the cars running - there should be around 13.5-14.5v across the battery. I‘m sure the alternator will be fine - but worth double checking while someone has the equipment to hand. 

shaun_from_Africa

It could well be the original. When I bought the car I currently have, I traded in a 12 year old car and this still had the factory fitted battery.
If it is the original battery then to be honest, I wouldn't even waste time trying to recharge it and just buy a new one.
Even if it not original but still more than about 4-5 years old, I would do the same.

If you have a look on the battery itself, there may well be a manufacturing or initial charge date written on it but if it is 11 years old, there is a good chance that this will be impossible to read unless it's engraved on.

tberry6686

just had the same thing with the missus car.  7 year old battery killed off by lack of use over the last couple of months.  Charging the battery got a days use but wouldn't start again next day - 11.2V accross the terminals in the morning.  with engine running 12.9v across the terminals.  New battery from ebay, with engine running 13.5 V.

Avoid halfords for a battery - overpriced.