TMC is an independent, primarily volunteer organization that relies on ad revenue to cover its operating costs. Please consider whitelisting TMC on your ad blocker or making a Paypal contribution here: paypal.me/SupportTMC

12voltBatteryCharging

Discussion in 'Roadster' started by Botbldr45, Jun 28, 2014.

  1. Botbldr45

    Botbldr45 Member

    Joined:
    Oct 11, 2011
    Messages:
    513
    Location:
    Sedona, Az
    From many posts on various threads I was led to believe that the 12 volt battery was recharged by the main battery pack in the roadster. I'm not really sure how I got that impression but recently service in Bethesda told me there is no trickle charging of the 12 volt. It just sits there and discharges over time until it fails and leaves you stranded. I asked them if they replace the battery at yearly service and Jonathan said, "No!". He told me that mine was "tested" and it still was putting out 12.7 volts. My battery testing of a separate 12 volt battery for my LED project shows me that the battery will continue putting out over 12 volts with minor fade until it crashes. Raises concern".........:scared:

    Anybody know if Jonathan is correct. Is there no trickle recharging on our Roadster batteries! If not... Can they be recharged by, say a Lotus Battery Minder? Should they have a voltmeter on them to monitor SOC?
     
  2. Doug_G

    Doug_G Lead Moderator

    Joined:
    Apr 2, 2010
    Messages:
    15,848
    Location:
    Ottawa, Canada
    Nonsense. There is an inverter that charges the battery from the main pack.

    These batteries have a lifetime. In my experience, under moderate usage they last a couple of years.
     
  3. Botbldr45

    Botbldr45 Member

    Joined:
    Oct 11, 2011
    Messages:
    513
    Location:
    Sedona, Az
    Thank you .... I thought I had heard that before.
    First two years I went in for service they changed the battery. This time they did not and that's why I asked the Service Rep.
    Guess it's still safe then. I had better read up on what to do when it fails..... I think you just open the charging port door, starting the main circuits and then call service for a new one.
     
  4. smorgasbord

    smorgasbord Active Member

    Joined:
    Jun 3, 2011
    Messages:
    2,379
    Location:
    SF Bay Area
    I just had my three year annual service - over 30K miles. It has the original battery, and I specifically asked them to check it. They say it's fine and did not replace it. I bought the extended warranty to carry me forward another 3 years, btw.
     
  5. Doug_G

    Doug_G Lead Moderator

    Joined:
    Apr 2, 2010
    Messages:
    15,848
    Location:
    Ottawa, Canada
    Mileage may vary. Probably also depends on climate, usage patterns, etc. And probably some unit-to-unit variability in their durability also. (I've used similar batteries for other purposes... some seem to last longer than others.)
     
  6. Botbldr45

    Botbldr45 Member

    Joined:
    Oct 11, 2011
    Messages:
    513
    Location:
    Sedona, Az
    I will be hitting the magic number this summer and have been agonizing about the extended warranty. Did you get both battery and general? Oh, and what is your CAC?
     
  7. Kevin Sharpe

    Kevin Sharpe Active Member

    Joined:
    Jul 29, 2010
    Messages:
    1,761
    Location:
    Bradford on Avon, UK
    #7 Kevin Sharpe, Jun 29, 2014
    Last edited: Jun 29, 2014
    My car is 4 years old on July 1st and I've driven 55,254 miles. CAC was 129.46 on June 24th.

    I took out the extended warranty and have been really glad that I did. I had a motor bearing fail at 50,500 miles (December 2013) requiring a motor replacement, and the car is currently in the workshop with "Powertrain Problem Service Required" after it shutdown and refused to move. I love the Roadster but without the extended warranty it would be costing me serious money. I also suspect that without the warranty I'd be at the back of the queue with no leverage given the workshop is overloaded by Model S deliveries in the UK (that said, my car has already sat in the workshop for a week without any attention from Tesla).
     

Share This Page