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Comment by throwahey | Hacker News Reader

The 60kWh models with 75kWh battery packs were only sold for a brief period of time, I think their logic was that it cost less to produce a single battery pack for both the 60 and 75. They were identical with the exception of the software limit.

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The capacity of all Tesla batteries is larger than the stated one primarily to hit their battery life span targets people who took them apart during salvage report about 15-20% potential higher capacity. It’s essentially the same overprovisioning we do with hard drives and SSDs.

Here is the EPA filing for the Tesla Model S 60 which shows a 65.9kw/h and a 95.5kw/h for the 85/85D. (based on the filing date of 2013..)

https://iaspub.epa.gov/otaqpub/display_file.jsp?docid=31841&...

These are dyno load tests (on the battery) not the actual road/drive tests which are used for the final classification of the car this one is used for the classification of the power train only.

As other people have noted in this discussion, the curve of battery capacity over time does not jive with an overprovisioning strategy.

Both HDDs and SDDs show no almost no degradation until they suddenly have a ton of degradation. (I've owned 3,000 SDDs, 15,000 HDDs, and 1 Model S.)

It doesn’t jolt with their EPA filings which indicate higher capacity for each model time and time again I’ve linked to one from 2013 below and it’s the same story every time.

The degradation pattern is ofc different because SSDs or HDDs are essentially binary the sector or cell is either good or bad and when you go out of spare sectors you are screwed.

Also most of them have many other modes of failure which do not involve their primary capacity.

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