Battery life of 120Ah

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Instacar7er

Active member
Joined
May 26, 2023
Messages
25
I read somewhere that these batteries give about 100k miles and it’s about $12k to replace? That correct?
 
Instacar7er said:
I read somewhere that these batteries give about 100k miles and it’s about $12k to replace? That correct?
Evidence suggests that a 120 Ah battery pack will continue to function well way past 100k miles. Recurrent Auto has monitored over 15,000 EV's over 200,000,000 miles. Recurrent has documented that EV battery cell degradation tends to follow an S-curve with some initial degradation followed by a long period of little degradation until the battery cell essentially wears out. At 120,000 miles, a typical EV battery pack remains in the long period of little degradation with much useful life remaining.

The manufacturer of an i3's battery cells, Samsung SDI, published this spec sheet for the 94 Ah battery cells used in 2017-2018 i3's. It estimates 4,600 charge-discharge cycles before the capacity degrades to 80% of its new capacity. That's equivalent to over 500,000 miles of driving! A larger capacity 120 Ah cell should power an i3 even farther.

Samsung-SDI-94-Ah-cell-specs-3-13-scaled-1.jpg


I don't know the replacement cost and don't recall reading about any 120 Ah i3 owner who had to replace the battery pack. I don't worry at all about having to replace the battery pack in our 120 Ah i3. I wouldn't trust the source who wrote what you read because there's no reason to believe that it's true.
 
alohart said:
Instacar7er said:
I read somewhere that these batteries give about 100k miles and it’s about $12k to replace? That correct?
Evidence suggests that a 120 Ah battery pack will continue to function well way past 100k miles. Recurrent Auto has monitored over 15,000 EV's over 200,000,000 miles. Recurrent has documented that EV battery cell degradation tends to follow an S-curve with some initial degradation followed by a long period of little degradation until the battery cell essentially wears out. At 120,000 miles, a typical EV battery pack remains in the long period of little degradation with much useful life remaining.

The manufacturer of an i3's battery cells, Samsung SDI, published this spec sheet for the 94 Ah battery cells used in 2017-2018 i3's. It estimates 4,600 charge-discharge cycles before the capacity degrades to 80% of its new capacity. That's equivalent to over 500,000 miles of driving! A larger capacity 120 Ah cell should power an i3 even farther.

Samsung-SDI-94-Ah-cell-specs-3-13-scaled-1.jpg


I don't know the replacement cost and don't recall reading about any 120 Ah i3 owner who had to replace the battery pack. I don't worry at all about having to replace the battery pack in our 120 Ah i3. I wouldn't trust the source who wrote what you read because there's no reason to believe that it's true.
Wow!!! Thank you! As I was looking to buy an i3s I was concerned for the existing mileage and what was left for me to use before the batteries need replacing. I saw a ‘19 i3s going for 25k that had 42k miles and thought almost half of its life was gone. No one wanted that so that is why it was so cheap and has been on the lot for so long!
 
My 90 Ah battery in a recently purchased, 2017 BMW i3-REx, came in at 28.4 kWh and delivers 106 mi range at 65 mph on a Standard Day. This is car is approaching 56,000 mi after six years.

My 2019 Tesla Model 3 Standard Range Plus at 115,000 miles has between 47-48 kWh of the original 55 kWh. It indicates 215 miles range. Sad to say, I learned a valuable lesson about parking in +90 F that resulted in a tow. When the 'Guess of Meter' says you are half a mile short, believe it.

Bob Wilson
 
Modern EV batteries are lifetime components. Gone are the days of old chemistry and poor BMS software requiring frequent battery replacement. These cars aren't like early prius or Honda Insights. There will of course be manufacturing hiccups like with Bolt but you really don't need to worry about battery life if the car is predicting good range.
 
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