Hello All

I have a FEH 2005 which was left in the bitter Canadian cold for 20 days and now the 12V battery is completely dead

Is there any special procedure that I should follow to jump start it? I have CAA premium membership....can I rely on them to help or should I be using special assistance for a hybrid? Also, assuming the jump start does manage to start the car....will the High voltage battery be dead too?

Please advise....I might also add that the Car has a remote starter installed and to disable it and use the regular key start I would need the 12V batter to be live.

Any assistance will be greatly appreciated.

Thanks in advance

Anish

 

First, you need to check out the 12v battery. If it really went fully dead, its probably frozen. Frozen = unrecoverable.

I suspect the HV battery will be fine. Put in a new 12v battery and I believe it will start up no sweat. The 12v battery only operates the main power contactors so it doesn't need the oomph of a 12v battery used in non-hybrid car.

 

Thanks Bill for your response....
I am a complete novice....can you please let me know how I can check if the battery went completely dead?

When I put in the key and switch it on nothing happens!

Thanks
Anish

 

Put a low amp, 2-4, charger on the battery, it can take up to 3 days to recover a fully discharged battery and remember that at teh same time there is a DC-DC inverter that if need be will be restoring the charge on the hybrid battery.

 

First check to see if the battery is frozen. Look in the caps (wear eye protection - that's sulfuric acid down there). If you think it is then bring it in the house and let it stand for a day to thaw out. Only then should you charge it. No response from your car says its dead.

Don't, repeat don't, charge a frozen battery.

 

It's not a maintenance free battery??

 

These days most battery chargers will "ramp-up" the charge rate in accordance with the battery's internal resistance. A full discharged Lead-Acid battery will initially have a HIGH resistance to charging which is why it might take several days to restore a battery to the point wherein it will accept a full charge.

The other method might be to put a 2 amp (23W) trickle charger on the battery and then just wait....

 

Maintenance Free Battery? What's that got to do with it. Some of those don't have removable tops/caps etc. But as far as freezing is concerned makes no difference.

The statement about high resistance is just not true. Battery charging rates are a function of 1st the difference between the applied voltage and the battery's voltage. The larger the difference the larger the charging current. Then 2nd the internal resistance is considered.

A fully discharged battery will have a high charging current since the voltage difference will be large.

As far as this case is concerned the initial statement makes me think it probably froze. If it did then thaw it out completely before charging it. You risk an explosion if you try to charge it frozen.

 

Maintence Free have no removable caps as you stated that's my point.

 

"..will have a high charging rate since the voltage difference will be large..."

Take a modern battery charger and hook it to a fully discharged battery and watch the charge rate rise from zip/zilch/zero as the chemical composition of the electrolyte changes. Yes, the voltage, LOW voltage, across the terminals of a fully discharged battery would certainly imply a high charge rate. But in reality it's the internal resistance of the battery that dictates the charge rate.