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

Question about battery mgmt in hot weather

Discussion in 'Model S: Battery & Charging' started by Gear, Jul 14, 2013.

  1. Gear

    Gear Member

    Joined:
    Jul 14, 2013
    Messages:
    594
    Location:
    SoCal
    Hey guys. I'm new here and have been considering getting rid of my BMW 335d for a P60. After reading through the recommended charge percentage thread, it seems SOC and temperature are the major factors for battery life. I live in the mountains of SoCal so it's relatively cool year round and my car stays in the garage. My concern is that my car routinely sits outside in 105 heat in the summer while I'm at work. Is this going to murder my battery before the 8 years is up, even if it has a ~60% SOC at the time? I have a 25 mile drive home which isn't a big deal, but it's a +3000ft elevation change so it would likely need a decent charge level while it sits. Any help is much appreciated.
     
  2. Jason S

    Jason S Model S Sig Perf (P85)

    Joined:
    Apr 20, 2012
    Messages:
    1,350
    Location:
    Rocklin, CA
    Tesla is really good at battery management. If you anticipate replacing your car in the next year or so, the P60 might be a good replacement.

    Heck with a 50 mile round trip plus another 20 miles lost to elevation change (overestimate), you only need half the current pack for comfort. So it'll be fine.
     
  3. DaveVa

    DaveVa Sig Perf #236 VIN #484

    Joined:
    May 31, 2011
    Messages:
    280
    Location:
    Northern Virginia
    While you should be fine, but if you can afford to upgrade to the 85, you will never regret having extra miles for un expected events.
     
  4. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

    Joined:
    Mar 8, 2012
    Messages:
    12,752
    Location:
    Texas
    I wouldn't worry. The Roadster experience is that temperature doesn't really affect the Tesla battery much due to the thermal management. The Model S has more advanced thermal management than the Roadster. However, I'll second the "If you can afford it, get the 85 kWh battery", extra range never hurts.
     
  5. Gear

    Gear Member

    Joined:
    Jul 14, 2013
    Messages:
    594
    Location:
    SoCal
    It's not really a matter of being able to afford it or not. I can afford it, I just don't know if I can justify it... I figure I put about 15k a year on my cars, so that puts me right at the 125k miles for the warranty after 8 years. I don't live near a supercharger either nor does it look like I will anytime soon. 10k is a lot of money for 60 miles.
     
  6. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

    Joined:
    Mar 8, 2012
    Messages:
    12,752
    Location:
    Texas
    It's more than the 60 mile increase. It's also quicker, and each cell will be less stressed as there are more cells to spread the load around.

    I wouldn't worry too much about passing the 8 year warranty. It's not like the the battery will die at 8 years and one day. Someplace there is a quote from Elon saying that the battery was designed to last double the warranty. The one thing I've learned in 250,000 miles of Prius driving is that the large battery is a non-issue (the 12V battery is another story).
     
  7. spleen

    spleen Active Member

    Joined:
    Jul 7, 2012
    Messages:
    1,125
    Location:
    Honolulu, HI
    Just a nitpick to clarify nomenclature - usually the P in front of the battery size refers to "Performance". So, a P85 refers to a Performance 85 versus a S85 which is a standard 85. A P60 doesn't exist because there's no Performance 60 (though maybe there should be!) - usually we just refer to it as a 60. Not that it really makes much difference in this case but just for clarity's sake and to avoid confusion in the future ... :smile:

    As for the 60 vs 85 discussion, I'd agree with Jerry - if you can afford it, the 85 is less likely to cause range anxiety, gets you supercharging in case things get built out more eventually, and results in less stress on the battery. The added performance is a bonus. :)
     
  8. DonL

    DonL Member

    Joined:
    Jan 30, 2013
    Messages:
    29
    Location:
    La Jolla, CA
    Battery

    You might want to consider the 85kwh due to the unlimited warranty: "
    The warranty includes eight years unlimited mileage for the Model S’s 85 kwh battery pack and eight years or 125,000 miles for the 60kwh pack (whichever comes first)'
    \
     
  9. Gear

    Gear Member

    Joined:
    Jul 14, 2013
    Messages:
    594
    Location:
    SoCal
    My mistake. I actually knew that, but had a temporary brain fart as in my other love (motorcycles) "S" generally means "Sport." That's my excuse to justify my mistake anyway. :)

    - - - Updated - - -


    I understand that, that's why I pointed out that I doubt I'll exceed the 125k miles in the 8 years. :)
     
  10. ModelS8794

    ModelS8794 Member

    Joined:
    Nov 29, 2012
    Messages:
    404
    Location:
    PA
    #10 ModelS8794, Jul 14, 2013
    Last edited: Jul 14, 2013
    Everybody jumped on the 60 v 85 argument instead of actually answering this question!

    I do not beleive the battery life will be affected at all by having the car parked outside during your work day. the thermal management system will keep the battery at optimal temperatures, and the worst that will happen is the car will use more juice to keep the battery cooler during those hot days left parking outside. Additionally, the HVAC in the summer will add some burden to your energy usage, so your total efficiency will be impacted by the use case you articulate and you may find yourself not achieving the EPA range... on the other hand you may just enjoy driving with more exuberance and not meet the EPA rated efficiency for that reason... it all comes out in the wash really. Unless you have a fairly frequent need for >150-175 miles driving daily, you should be perfectly fine in a 60 even 150,000 miles down the road. for a 50 mile round trip commute it's no issue whatsoever IMO. Sure the 85 will be a bit faster, and the P85 a bunch faster than that too... but you won't be complaining with a 60, it's nt like that trim level is uderpowered or anything!

    Good luck with your decision.

    edit: by the way, elsewhere in this forum members have concluded that elevation costs about 7 miles of range for every 1000' you climb (and you get back less than 4 miles for every 1000' you descend if you maximize the use of regenerative braking). So your 25 mile drive home climbing 3000' would necessitate about 40 miles of range, call it 50 miles once you consider your hot summer days and perhaps heavier HVAC usage. In a 60, you'd likely want to get in the habit of plugging in every evening, but you should feel comfortable setting your recharge to 80-90% no problem... no need for a full 100% charge level on a regular basis (which WOULD likely impact battery life)
     
  11. VolkerP

    VolkerP EU Model S P-37

    Joined:
    Jul 6, 2011
    Messages:
    2,455
    Location:
    Germany
    @Gear why not hit two birds with one stone? Push for solar canopies where you park at work. Offer a financial contribution. Research incentives for the property owner to go solar.

    Your car will hold its charge much better when parked in the shadow. And you will find it much more comfortable to enter it. If you charge at home, it is your money that gets spend running the AC for the battery and for preconditioning the car. So there is some minor financial benefit for you to do this push.
     
  12. PhilBa

    PhilBa Active Member

    Joined:
    Apr 20, 2013
    Messages:
    1,355
    Location:
    Seattle
    I think there was a study released at Teslive where the average roadster battery at 100K miles functioned at 80-85% of it's original capacity.

    Prius 12V battery - lol, just had to "jump" my Prius the other day. Third time in 5 years. I think my kid didn't turn it off or something.
     
  13. TSLA Pilot

    TSLA Pilot Member

    Joined:
    Mar 12, 2013
    Messages:
    302
    Location:
    United States
    Went from a 2011 BMW 335i to the Model S 85 so I'm familiar with your current wheels.

    Recommend the 85 as the performance is better than the 60 kWh, plus it includes SuperCharging at no cost, for a net difference of only $8k. Even if a SC isn't local now, they likely will be in a few months/years (think resale!).

    Regardless, either the 60 or 85 will surprise you with their excellent performance.

    Enjoy your new Tesla!
     
  14. Gear

    Gear Member

    Joined:
    Jul 14, 2013
    Messages:
    594
    Location:
    SoCal

    I doubt there will be one near me anytime soon as I live in a small secluded town. The only times I'd have use for one would be driving to Vegas or LA, which happens maybe twice a year. I really would like the 85, but I just don't understand the $8k difference when the whole pack only costs $12k.
     
  15. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

    Joined:
    Mar 8, 2012
    Messages:
    12,752
    Location:
    Texas
    The cells in the pack may only cost $12K (I'm pretty sure that's the only thing included when folks talk about the cost of batteries), but there is also assembly, the additional parts that Tesla adds, distribution costs, and profit. The actual Tesla battery pack is far more than $12K.
     
  16. Gear

    Gear Member

    Joined:
    Jul 14, 2013
    Messages:
    594
    Location:
    SoCal
    #16 Gear, Jul 14, 2013
    Last edited by a moderator: Jul 25, 2013
    From what I read, $12k was the replacement cost.
     
  17. bollar

    bollar Disgruntled Member

    Joined:
    May 1, 2013
    Messages:
    2,240
    Location:
    Southlake, TX
    You're right, it must be more than $12K.

    Last year, Tesla quoted $12K as the replacement cost of the 85 kW battery, but in other documents said that there was residual value to the exchanged battery and expected to make money on those transactions. They were also probably taking declining battery prices into account, so maybe $25K now and 18K in four years?
     
  18. hans

    hans P631

    Joined:
    Sep 27, 2012
    Messages:
    1,123
    Location:
    Menlo Park
    I have an S60 and it's every bit as fast as an S85. It's lighter, handles the turns like there is one less passenger worth of weight in the car. 0-45mph is every bit as fast or faster than a 85 kWh car. If you need the range, go for an S85. It you want performance, go for a P85 or P85+. Don't buy an S85 over an S60 for performance reasons. The differences are imperceptible other than range.
     
  19. Zythryn

    Zythryn MS 70D, MX 90D

    Joined:
    Mar 18, 2009
    Messages:
    1,660
    Location:
    Minnesota
    Yes, it is, however that is replacement in 8 years. In addition to prices coming down in that time, the old pack will still have value (grid or house backup come to mind).

    However, as an owner of both a 85 and 60, I disagree with others here. If you don't foresee needing the range, I would not push to get the 85. The performance difference is tiny and the 60 seems to be more efficient.

    I would suggest test driving both to try for yourself.
     
  20. Gear

    Gear Member

    Joined:
    Jul 14, 2013
    Messages:
    594
    Location:
    SoCal
    Thanks. You seem the perfect person to know! Part of my rationale for sticking with the P60 is that when I went for my test drive, they said the P60 owners would be able to rent the 85kWh batteries as part of the battery swap program. So if I were really needing the range, I could swap it temporarily. She said the swap would be "less than a tank of gas" so that seems promising. Also, if I decide later that I need supercharger use, I can add it (though for $500 more than if I did it right away).
     

Share This Page