[RahulNagaraj]

It was long believed that frequently fast-charging vehicles is bad for their battery's longevity. Tesla even warned their users against it. However, a new study shows that Tesla battery degradation isn't accelerated by frequent supercharging.

The study conducted by Recurrent is said to have access to data from over 12,500 Tesla vehicles in the USA. The study states that there is little to no difference in battery degradation between cars that frequently fast-charge to those that rarely fast-charge.



Recurrent stated that they focussed on extreme use cases, comparing Tesla cars that fast charge 90% vs. those that fast charge only 10% of the time. The results showed no significant differences in range degradation. Reports also state that the Tesla owner manual doesn't mention battery degradation being affected by frequent fast charging anymore. Instead, it just mentions the potential to "slightly decrease" the peak charging rate.

The study stated, "The peak charging rate of the battery may decrease slightly after a large number of DC fast charging sessions, such as those at Superchargers. To ensure maximum driving range and battery safety, the battery charge rate is decreased when the battery is too cold when the battery’s charge is nearly full and when the battery conditions change with usage and age."

The study does warn about fast charging under extreme heat or cold conditions though, as it is not said to be ideal for battery performance.

Source: Electrek

Link to Team-BHP news

[anshumandun]

Another day and another study on EV technology. What a dynamic time to live in, in terms of evolving automotive technologically.

If true, this is really good news for EVs. Many myths about battery degradation are being demolished study after study.

[RMN]

Will these improvements in EV battery technology trickle down to consumer electronics soon? Doesn't seem like batteries have made any significant improvements over the last 5 to 7 years on the smart phone space at least.

[Shresth_EV]

Originally Posted by RMN

Will these improvements in EV battery technology trickle down to consumer electronics soon? Doesn't seem like batteries have made any significant improvements over the last 5 to 7 years on the smart phone space at least.

It’s a grossly incorrect oversimplification when people say “EV batteries will only last same as phone ie 2-3y”

And it’s a extremely unfair and rigged-to-fail comparison to expect similar life out of phone/laptop battery as an EV, because the former does not have half the sophistication as the latter due space and weight constraints.

We cannot just compare the two batteries because they’re same type (lithium anode) and even then, without knowing exact chemistry, (ie LFP, NCA, NMC, LTO) it’s a futile exercise. Most people apply 2+2 = 4 logic when they see “oh both are lithium battery, they must be EXACTLY identical”, without considering the nuances.

To demonstrate differences :

Phone vs EV :

Daily charged from 20-80 (or worse 0-100) VS
Daily charged 60-80 (rarely depleted fully on daily basis, 85-100 for our Nexon doing 40km daily)

Does not have battery temp management VS
Has Liquid active temp management (heat reduces SoH)

Single cell designs (10-15Wh) being charged at 20W or more
VS
Nexon EV having 630 cells of 48Wh with each cell being charged at 4.5W/33.3W (2.8kW/21kW divided bw 630 cells)

Designed cycles 500 (~1.5y to reach 80% SoH in worst case)
VS
2000 designed cycles (5.5y to reach 80% SoH in worst case ie 0-100 daily) 2000 cycles = 300,000km on odo for Nexon EV (150km range worst case)

The most important part to notice is cooling systems and the third being the actual C rate of charging. Even fast charging an EV uses less C rate than my laptop which charges at 67W for a 70Wh battery or my phone which takes 15W for a 10Wh battery.

The second is the usage pattern, phone or laptop is pretty much exhausted after a full workday but even with 50km commute, EV will only exhaust 1/4th of its battery (Nexon)

Consequently, my phone will give out first (no cooling, high C rate), followed by my laptop (some cooling, slightly lower C rate) and my EV last (liquid cooled and slowest C rate)

[GTO]

Would it be safe to say that not all batteries are created equal? From what I have read, Tesla's batteries, battery management software & EV technology are absolutely top-game. So, they are more robust & reliable?

Perhaps, fast charging could detrimentally affect the batteries of other carmakers? Especially the cheaper & mainstream models?

[extreme_torque]

Originally Posted by GTO

Would it be safe to say that not all batteries are created equal? From what I have read, Tesla's batteries, battery management software & EV technology are absolutely top-game. So, they are more robust & reliable?

Although Tesla has their own battery chemistry IP, it is their systems which are their USP especially the data driven approach that they have for everything. They have access to huge amount of fleet data given million of connected Tesla's already on the road and they use that data to improve their systems and subsystems but also effect user behaviour.

As an example - when I first got my Model Y Performance, the car would recommend charging upto 90% for everyday driving which was changed to 80% a couple of weeks back. I am sure this has to do with the data they have for the fleet. Also, their built in diagnostics or the service menu is top rate and shows how integrated their system is. Posting some photos of the diagnostics menu just to give everyone an idea

[volkman10]

Would you replace a Tesla Model 3’s battery for $12K or sell as is for $16K?

The three-year-old EV has been driven 150,000 miles but the battery already has "worn-out cells near depletion"

he bought his Tesla Model 3 in September 2020, and has since driven it “extensively” on road trips and for ride-sharing. Unfortunately, he recently got a notification saying “Charge limit and range reduced request service soon – OK to drive”. Shortly after that, he got a call from a Tesla service representative, suggesting that the battery should be replaced soon due to “various cells being worn out and near depletion”.

The battery health status is currently at 81%, but the worn-out cells could soon limit its ability to charge, meaning that a replacement is the only viable option if someone intends to keep the car. The Tesla is out of warranty and the cost of a battery replacement is a whopping $12,000

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