Daily supercharging kills Model 3 battery in 120,000 miles

[OVERKILL]

Interesting experience here:
https://www.forbes.com/sites/brooke...ercharger-after-model-3-dies/?sh=71bb0188473c

Backdrop: The driver, Dobson Omene, runs a transportation service in Atlanta, Georgia. His Model 3 battery died after 120,000 miles. At the time of the failure, he typically used a Tesla Supercharger — generically referred to as a fast charger — twice a day.

Omene knew something was wrong when the range on his Model 3 dropped suddenly from 170 miles to 35 miles. Long story short: Tesla replaced his battery but at a cost of $9,000 because he was out of warranty.

“The problem is you have a lot of rideshare drivers who have switched from a gasoline car to a Tesla because of the promise of saving money on gas", Omene told me in a phone interview.

They quote site darling Sandy Munro:

“That type of cycling will definitely kill a battery,” Munro said, referring to constant discharging and charging of batteries.
“Battery degradation happens for a lot of different reasons but mostly it’s cycling,” Munro said. “I think he cycled it to death.”

Home charging is best, Munro says. “Charging at home with a Level 2 charger...batteries like that the best,” he said. Level 2 is a slow charge and it typically takes several hours or more to charge a battery using level 2 chargers.

“The higher the charge is, then things start to happen,” he said. Fast chargers used by Tesla and Electrify America can charge at rates above 200kW while a level 2 charger typically charges no faster than 19kW.

Conditioning is also important.

“Conditioning the battery makes a big difference,” Munro said. In extreme heat or cold a battery needs to be preconditioned before charging. Not doing this could eventually cause problems. “It’s just like the guy who doesn’t want to change his oil.”

Dr. Bharat Balasubramanian, who worked R&D at Mercedes:

“Somewhere around 4c [charging rate] the battery starts getting permanent damage,” Dr. Balasubramanian said. The rate of 4c refers to fast charging rates where a car gets a full fast charge quickly.

“If you charge it at 110 kilowatts, you will be charging it at 1c. If you charge it at 220 kilowatts, you're charging it at 2c...and so on,” he said.

Balasubramanian said EV owners today rarely charge above those rates. But in general constant fast charging is not a good idea, he said.

“No one really knows how much damage the battery is going to take if you constantly fast charge but certainly it is going to get damaged,” Dr. Balasubramanian said.

Another problem when trying to pinpoint charging damage is that the evidence is, on the whole, anecdotal, Balasubramanian says.

“No one is going to be able to offer you real scientific evidence because if you want to do all these degradation studies, you have to do it scientifically in a large statistical patch,” he said.

“And by the time you finish all this, the battery chemistry has moved on to something else. So whatever you produce, someone else is going to say, no, we have changed the chemistry.”

“But, again, if you fast charge twice a day, I can certainly say you are asking for trouble,” Balasubramanian said.

This is one fundamental difference between fuelling an ICE and charging a BEV. No matter how fast you put fuel in the tank of your ICE, you aren't risking damaging it. On the other hand, the pursuit of faster and faster fast charging has significant negative repercussions for the battery, but it is being pursued regardless, because people are impatient and want it charged NOW.

 

[TheOilWizard]

120,000 miles? That's about the age BITOG members consider buying a vehicle.

$9,000 to replace the battery... ouch.

 

[Passport1]

Not exactly analogous to overcharging an EV but there are a couple of ways that an ICE vehicle can be damaged by gasoline. Letting a fuel injected car run dry may affect the electrical fuel pump. Overfilling the tank can cause evap system problems.

 

[OVERKILL]

Not exactly analogous to overcharging an EV but there are a couple of ways that an ICE vehicle can be damaged by gasoline. Letting a fuel injected car run dry may affect the electrical fuel pump. Overfilling the tank can cause evap system problems.

Neither of those things cost $9K to fix though. A fuel pump is a few hundred bucks typically, a carbon canister even less than that.

 

[JeffKeryk]

And yet other studies are reporting different results.

 

[IndyIan]

I wonder what the manual says on supercharging?
Also at 33mpg lifetime average for my Focus and an average fuel cost of $.14/mile my car has cost $16800 CDN in fuel alone for 120k miles... Plus $5-600 in oil changes. I wonder how much they spent on charging?
I'd guess a Prius would still have a similar fuel bill around $9k USD for 120k miles

I've been thinking about an old Model S with free charging, which could start to be worth getting even with the cost of battery included.

 

[OVERKILL]

And yet other studies are reporting different results.

Nobody in that study exclusively fast charged their car twice a day though, and they note at the bottom:

When is fast charging more likely to cause damage? There are several times when fast charging may impact your EV battery more. Avoid fast charging in extreme heat without preconditioning your battery. Preconditioning is when the car’s thermal management system pre-cools or heats the battery to accept a higher charge rate.

Typically, the battery will be preconditioned if you set your car’s navigation to a fast charge station. Similarly, precondition the battery before fast charging in extreme cold. Driving a bit before fast charging is often enough to warm up the battery or get to the fast charger using your car’s navigation. Avoid fast charging your EV at very low states or very high states of charge since battery resistance will be higher.

Overall, this study adds to the growing body of knowledge regarding EV battery longevity and charging practices. Nonetheless, being mindful of battery health during extreme temperatures is still encouraged.

So, perhaps rideshare operation (this usage profile) doesn't allow for accommodating those caveats, hence his experience.

 

[2strokeNorthstar]

I wonder what the manual says on supercharging?
Also at 33mpg lifetime average for my Focus and an average fuel cost of $.14/mile my car has cost $16800 CDN in fuel alone for 120k miles... Plus $5-600 in oil changes. I wonder how much they spent on charging?
I'd guess a Prius would still have a similar fuel bill around $9k USD for 120k miles

I've been thinking about an old Model S with free charging, which could start to be worth getting even with the cost of battery included.

When I rented a Tesla it was between $12-$20 to supercharge about +60% which is about 120-150 miles. Not exactly free.

 

[97prizm]

And yet other studies are reporting different results.

Yet they are Tesla supporters and post all Tesla is good. Not really a good way to extract information. The first article is from a Tesla owners own account.

 

[mk378]

How many miles per day? It's not designed for that sort of duty cycle.

The rideshare business model is based on the drivers not realizing the true cost of putting so many miles on their car.

 

[JeffKeryk]

Yet they are Tesla supporters and post all Tesla is good. Not really a good way to extract information. The first article is from a Tesla owners own account.

Yeah, Tesla owners tend own Teslas... Tesla data tends to come from Teslas, right?

 

[OVERKILL]

I wonder what the manual says on supercharging?
Also at 33mpg lifetime average for my Focus and an average fuel cost of $.14/mile my car has cost $16800 CDN in fuel alone for 120k miles... Plus $5-600 in oil changes. I wonder how much they spent on charging?
I'd guess a Prius would still have a similar fuel bill around $9k USD for 120k miles

I've been thinking about an old Model S with free charging, which could start to be worth getting even with the cost of battery included.

Looks like SuperCharging is anywhere between $0.25-$0.50/kWh. The Model 3 uses 23.53kWh per 100 miles according to InsideEV's, and so he's used 28,236kWh, so the cost for electricity for this guy is between $7,059 and $14,118 USD.

 

[350Rocket]

Not exactly analogous to overcharging an EV but there are a couple of ways that an ICE vehicle can be damaged by gasoline. Letting a fuel injected car run dry may affect the electrical fuel pump. Overfilling the tank can cause evap system problems.

Both true statements. However neither one is something that should or needs to happen, on a regular basis. Only reason for overfilling is you have ocd and need the dollar amount to land on an even number, even though it's coming off a credit card. My old coworker did this and the purge valve did fail on our 2005 Silverado work truck that he would make me top up to the nearest dollar. Not sure if that was why or not.

 

[racer12306]

Fast charging cell phones kill their batteries, this isn't a surprise.

 

[The Critic]

Fast charging cell phones kill their batteries, this isn't a surprise.

Agreed. This is hardly a surprise - the fast chargers were always intended for occasional use, not daily use.

 

[alarmguy]

Fast charging cell phones kill their batteries, this isn't a surprise.

... and I swear to this day it drives me nuts how fast my Apple Watch 7 charges. Typically less than 30 minutes while I shower when about 30% left before dropping it on the magnet.
Apple induction charger REALLY heats up the watch. I know it's not good.

I slow charge my iPhone 13 with a 12 watt firewire plug. Now that I think about it maybe I should do the same with the watch go from 25 to 12... but that wouldnt be as convenient as I sleep with the watch on.

 

[k1xv]

Its fairly common knowledge that maximum useful life of a battery is compromised when it is charged as quickly as possible. So yes, you can recharge your battery as you eat lunch, but it would be better for the battery if you recharged it overnight, while you slept.

 

[racer12306]

... and I swear to this day it drives me nuts how fast my Apple Watch 7 charges. Typically less than 30 minutes while I shower when about 30% left before dropping it on the magnet.
Apple induction charger REALLY heats up the watch. I know it's not good.

I slow charge my iPhone 13 with a 12 watt firewire plug. Now that I think about it maybe I should do the same with the watch go from 25 to 12... but that wouldnt be as convenient as I sleep with the watch on.

I have a 44mm Watch 5 Cellular, got it brand new in Sept 2019. In the last few months I've really noticed a decline in battery life, so almost 4 years before it was noticeably bad. My next step is to fully turn off Cellular (I know it's supposed to be off if it's not in use, but that is an annoyance in itself because of the handoff time). I can get through a work day, but don't expect much else.

I use the 5w for both the watch and my iPhone 13 Pro Max. I use optimization for the phone but I turned that off for the watch because it wasn't aligning with my use, may be better now but it's been a couple years.

 

[SubieRubyRoo]

I wonder what the manual says on supercharging?
Also at 33mpg lifetime average for my Focus and an average fuel cost of $.14/mile my car has cost $16800 CDN in fuel alone for 120k miles... Plus $5-600 in oil changes. I wonder how much they spent on charging?
I'd guess a Prius would still have a similar fuel bill around $9k USD for 120k miles

I've been thinking about an old Model S with free charging, which could start to be worth getting even with the cost of battery included.

Yes, but if you’re going apples to apples you’d have to add the total cost of charging plus the $9k to replace the battery. I know fuel pumps fail, but knock on wood, I’ve driven well over 800,000 combined miles in my various vehicles over the past decade and never suffered a fuel pump failure.

On the flip side, if one were to have a truly valid use case for an EV (inner city living, etc) where the commute and daily use were 10-30 miles per day, 120k on an EV may last you 15-20 years. If you’re putting 200+ miles per day like @Direct_Rejection you'd likely rethink the EV proposition in short order.

 

[Barkleymut]

When I rented a Tesla it was between $12-$20 to supercharge about +60% which is about 120-150 miles. Not exactly free.

$20 will buy 6.5 gallons of 87 octane right now. 6.5 gallons x 22 mpg in my 2007 V8 Mustang will take me 143 miles down the road....
Interesting because I always assumed at least the electricity would be cheaper than gasoline.