Toyota Rav4 EV Forum
http://www.myrav4ev.com/forum/

ALL POSTS - 12-volt battery replacement
http://www.myrav4ev.com/forum/viewtopic.php?f=8&t=1738
Page 3 of 9

Author:  tgreene [ Sat Jan 16, 2016 5:04 am ]
Post subject:  Re: 12-volt battery replacement

z3scot wrote:
I checked my battery voltage with voltage meter in the lighter socket.
In the morning before starting it was 12.0 volts. According to the battery meter that is down to 50%.
Car is 20 months old. So looks like I need a new battery.


I find that my cigarette lighter voltage meter reads about 0.2 - 0.3 V lower than a voltmeter across the battery terminals. I see even higher voltage on the batter terminals if I disconnect one of the leads. There may be more life in your battery than you think - you need to measure the true open-circuit voltage.

Author:  z3scot [ Tue Jan 19, 2016 2:31 am ]
Post subject:  Re: 12-volt battery replacement

The dealer checked the battery with an official load tester, and it tested OK.
He showed me the results, it showed the battery was good (12.2 Volts, CCA was higher than min) but needed to be recharged. I told him it had been recharging for 40 min on the way to work, and should be fully charged. They need the battery the battery to show bad on the tester to replace it under warranty.

What is the battery failure symptoms of impeding doom? Or is everybody just replacing the batteries because they are worried that the car won't power up one day? If the battery was low when driving it seems that the DC-DC power from the traction battery would keep the vehicle going. Has anybody had the vehicle quit because of a bad battery?

-- Scott

Author:  TonyWilliams [ Tue Jan 19, 2016 6:56 am ]
Post subject:  Re: 12-volt battery replacement

CCA doesn't apply... 12.2 V is a bad battery.

Author:  n3ckf [ Mon Jan 25, 2016 5:44 am ]
Post subject:  Re: 12-volt battery replacement

i have a battery maintainer i hook up whenever the car is going to be left more than a couple days without running it. Whenever i hook it up, i always see that it charges the battery.

i just checked, mine was at 12.5Volts (at the battery terminals while attached to the car) and i know it was fully charged up today. (I had the car "on" for at least an hour today).

Unloaded, it will be higher than that.

Author:  Bassman [ Thu Feb 04, 2016 7:37 pm ]
Post subject:  Re: 12-volt battery replacement

My dealer just informed me that my 12 volt battery is bad. It will be 3 years the 21st of this month. I've never had an OEM battery go bad in that short of a time.

Author:  TonyWilliams [ Thu Feb 04, 2016 10:27 pm ]
Post subject:  Re: 12-volt battery replacement

Bassman wrote:
My dealer just informed me that my 12 volt battery is bad. It will be 3 years the 21st of this month. I've never had an OEM battery go bad in that short of a time.


Congratulations!!! That's pretty good for any modern day EV with Telematics (the battery sits a lot of the time not being fully charged). The worst thing to do to a 12 V lead acid battery is to not have it fully charged. That means 12.7 volts.

If your car is three years old and has not had the original battery replaced, I recommend doing that now .

Author:  JDP [ Thu Feb 11, 2016 12:34 am ]
Post subject:  Re: 12-volt battery replacement

Tony, are these batteries failing because there something different about the way the EV uses/charges the 12v battery than ICE cars (other than the alternator, I mean)? I notice my windows slow down when I turn off the car (just like ICE), so it seems like the battery is supported when on/ready. Why do you suggest a deep cycle type battery?

Author:  TonyWilliams [ Fri Feb 12, 2016 6:56 am ]
Post subject:  Re: 12-volt battery replacement

JDP wrote:
Tony, are these batteries failing because there something different about the way the EV uses/charges the 12v battery than ICE cars (other than the alternator, I mean)? I notice my windows slow down when I turn off the car (just like ICE), so it seems like the battery is supported when on/ready. Why do you suggest a deep cycle type battery?


The battery gets deep cycled by the BMS and telematics, which operate while the car is off.

You do not require "cold cranking", so deep cycle is perfect.

Author:  miimura [ Fri Feb 12, 2016 8:19 am ]
Post subject:  Re: 12-volt battery replacement

The e-Golf comes with an AGM battery, which I thought was interesting, so I did a quick search and Bosch sells a Group 35 AGM battery for around the same price as a Yellow Top. The Bosch claims 53Ah capacity and 4 year warranty while the Yellow Top claims 48Ah and 3 year warranty.

The Bosch battery I saw is carried locally at Pep Boys.

Author:  Michael Bornstein [ Fri Feb 12, 2016 8:52 pm ]
Post subject:  Re: 12-volt battery replacement

Will an AGM battery work in the RAV4? I thought they required a different charging system.

Page 3 of 9 All times are UTC [ DST ]
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
http://www.phpbb.com/