Tesla has not be able to tell me why my 5800 mile/8 month old MY has pronounced range loss even though I have been super easy on my battery (no DC charging whatsoever, only charged to 100% once, mostly operate in SOC range of 50-70% since short daily drives, non aggressive driving habits, moderate coastal CA climate, etc). Teslafi has my vehicle dead last out of 200 vehicles with a projected max range of 278 (vs EPA 326 rating). I have tried the recalibration efforts per other posts (deeper cycles, etc) but so far not working (will keep trying). Here's my question: While it might sound strange, I live on top of a hill and my drive home involves a steep climb of about 700 feet over about 1/2 mile. A Tesla mobile tech came out the other day to work on something unrelated and when I asked about my battery issue, he commented that "maybe" this steep hill ending every trip home might have something to do with the issue. Anyone have any thoughts on this? Any possible technical explanation?
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Battery Degradation Related to Hill Climb to Get Home?
- Thread starter jmichaels
- Start date
Can't answer your question but interested in the responses. As a comparison data point, I also live at the top of a hill with an almost identical elevation gain over the last 1/2 mile. I don't use Teslafi, but the Tesla app gives me a max estimated range of around 302 miles. I'm just over 6,000 miles in 7 months of ownership so close to yours as well. I've probably charged to 100% only a handful of times (supercharged maybe a dozen times) and have similar SOC range and driving habits. I do live in Oregon so weather is cooler here than in Orange County. From what I've gathered here, my lifetime wh/mi has been around 305 which seems higher than average, but I've attributed it to living on a hill.
Hmmm. On top of a hill as well - 1400 foot elevation change probably over the last 1.5 miles of my drive - although I have a few areas of 13% grades. My wh/mi is horrible. Slowly getting my average down since I took delivery last Friday, but lets just say 860 wh/mi seems to be common. It's cold (sub zero) and I have studded, winter tires too.
tstolze
Member
Just to clarify, we are talking about overall battery degradation, not range projection on a specific trip. Sorry if any confusion there. The fact that my max range est at 100% (only 278 miles) is dead last in the Teslafi fleet when it's a young vehicle and battery has been gently treated has stumped everyone. Nobody seems to have an explanation. The Tesla tech's thought about ending every drive with a steep incline was an interesting concept. So far, nobody has chimed in with a technical perspective. Hoping someone might have a thought or two... To have a 8 month old MY with 5800 miles that's lost 15% of battery capacity (326 to 278) doesn't make any sense.
Lucky you...how many miles on your vehicle? Can you share your other charging habits?
Our situation is similar yet my battery capacity/max range seems to be much less. My lifetime wh/mi is around 270...so less than yours. The only other thing I can think of is I had a streak of a lot of 65% and 70% charges and maybe that messed up my BMS. That said, I have been trying to recalibrate per the other posts...drain down low (to 10-20%) and charge high (85-90% ish) for a month or so. Doesn't seem to help (so far). What do you think your charge summary would look like if you had Teslafi? See below.
While the temperatures in your area are mild, your overnight lows are still fairly cold at 50F (especially for lithium batteries with less Cobalt). The sensitivity to the cold does impact the capacity/range of the battery temporarily. For this reason, I think it’s safe to assume that the BMS will eventually lose calibration with the true capacity as the battery spends more time at colder temps. I also think you will start to see the range start to recover once the outdoor temps warm up. After owning an i3 for over 4 years, I can definitely confirm that the predicted range does fluctuate between summer and winter, losing about 25% in the winter.
I’m a little surprised that the Tesla tech would suggest that. First of all, there’s not going to be a ton of heat generated from that kind of scenario with a Tesla. Even if there was, the BMS takes care of this by keeping things circulating for some time after the car has been parked. Maybe the tech was thinking about turbocharged ICE vehicles, which could be impacted by this scenario due to the heat that’s generated in the exhaust side of the turbocharger, which takes time to cool off and precautions should be taken to prevent a premature failure. A simple solution to this problem is a ‘turbo timer’ which keeps the circulation system or engine running for a few minutes after the key has been removed, similar to what the BMS is doing in a Tesla after parking.
I’m a little surprised that the Tesla tech would suggest that. First of all, there’s not going to be a ton of heat generated from that kind of scenario with a Tesla. Even if there was, the BMS takes care of this by keeping things circulating for some time after the car has been parked. Maybe the tech was thinking about turbocharged ICE vehicles, which could be impacted by this scenario due to the heat that’s generated in the exhaust side of the turbocharger, which takes time to cool off and precautions should be taken to prevent a premature failure. A simple solution to this problem is a ‘turbo timer’ which keeps the circulation system or engine running for a few minutes after the key has been removed, similar to what the BMS is doing in a Tesla after parking.
I have also taken exemplary care of my battery but have almost 9% degradation after 5 months and 9k miles. I pretty regularly cruise at 80mph with AC on full which is probably similarly taxing to the battery as driving uphill. Unless I got a lemon this is the only thing I can think of. I’ve never supercharged and have literally never been outside of 17-85% charge. The vast majority of days it goes to 80% at night and down to 50% when I get back home from work.
Just as an update now that summer is over for me and I've had more time behind the wheel. My average is around 330 wh/mi. 5500 miles on the car and my 100% charge typically shows 300 miles of range. I don't drive as fast as @Chewy986 does as speed limits are 60-65 mph here, but otherwise my operating/charging conditions are pretty close.
I don't think going up a steep hill will degrade your battery.
I've gone up and down the same mountains literally hundreds of times over the past 14 months. My energy meter is showing something like ~950 wh/mi avg for the ~7 miles up.
The GOM (guess-o-meter) rolled a 314mi around the time when I got my car (late June 2020).
At the ~1 year mark GOM rolled a 305mi when I probably had ~10k miles.
My car's lifetime average (~11k miles) is 248 wh/mi.
I've never charged to 100%. I've only charged up to ~90% and got down to 30%. I generally try to keep my battery between 50-70% overnight.
I've gone up and down the same mountains literally hundreds of times over the past 14 months. My energy meter is showing something like ~950 wh/mi avg for the ~7 miles up.
The GOM (guess-o-meter) rolled a 314mi around the time when I got my car (late June 2020).
At the ~1 year mark GOM rolled a 305mi when I probably had ~10k miles.
My car's lifetime average (~11k miles) is 248 wh/mi.
I've never charged to 100%. I've only charged up to ~90% and got down to 30%. I generally try to keep my battery between 50-70% overnight.
I use 15% of my battery each roundtrip into town in the summer and 20% or so in the winter. So if it dropped to 250 miles it still isn't a huge issue for me. I can still do everything I need to with the car. Once I switched to % is makes a lot more sense, even though I prefer to look at the miles remaining most of the time. (the next exit is never XX% away, it's always XX miles)
Always having the car sleep in the same state of charge range (example: 50-70%) can result in downward drift of the BMS calculation. It’s important that the car occasionally sleep with the state of charge closer to the extremes (example: 10%, 90%) in order to improve accuracy.
Sleep means several hours (overnight) with Sentry Mode, Smart Summon and Climate Keeper turned off and no apps or OCD owners constantly pinging the car.
Sleep means several hours (overnight) with Sentry Mode, Smart Summon and Climate Keeper turned off and no apps or OCD owners constantly pinging the car.
By the look of this chart this is most likely the cause of the BMS being out of sync. Set it at 90% or 80% and call it done. All those short charging sessions will most likely play a factor in the BMS.
Doubt the hill has anything to do with it, unless you're charging immediately upon arrival at home and the BMS calculation is just off from the climb. Honestly, switch to percent on your display, and ignore the battery report from teslafi. My battery has bounced all around on that graph in my 3.5 years of 3 ownership. I have never done any of the deep cycle stuff to try and recalibrate either, I think those suggestions are a waste of time. Just drive more, take a road trip, hit a supercharger, etc.... Eventually it will rebalance. Gotta ignore the short term wiggles.
I like to use percentage as poster above noted. Just allocate 2 miles per percent and the driving becomes less stressful. I’ve yet to ever look at the miles remaining and only use percentage. If I want to see miles remaining, I use the energy screen in combination with the “trip” feature.
I’ll bet it is the BMS as well. Even if the battery got hot going uphill, it’ll cool itself down with AC when you get home.
I’ll bet it is the BMS as well. Even if the battery got hot going uphill, it’ll cool itself down with AC when you get home.
Even less stressful if you can free your mind of ever thinking in terms of miles to begin with. I wish Tesla would switch the default display to percent. The nav directions used to show percent at destination right there with time at arrival. I wish they would bring it back. As it is, tap the header row to expand the directions and you'll see all you need to know. No need to convert to an arbitrary rated miles number at all, just trust the nav, keep an eye on it, worst case slow down if it drops below your comfort level.
