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Comment by vonklaus | Hacker News Reader

Does anyone know how long something like the new Tesla powerwall lasts? What happens after the useful life of the hardware, can they be recycled/fixed?

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The warranty lasts 10 years. It is basically guaranteed to work for ten years. This is probably analogous to the 60k mile warranty that comes with a Prius. Nobody is junking their Prius after 60 thousand miles.

Look at the press kit for more information.

http://www.teslamotors.com/presskit/teslaenergy?via=newslett...

I'm not sure about the specific chemistry used in Teslas thing, but consumer grade Lithium Polymer cells are usually quoted as maintaining 80% of initial capacity after 1000 charge/discharge cycles (when using proper recharging gear - sub $10 Chinese toys often ignore charge requirements altogether and trash or set fire to lipos within a few dozen cycles). Which fit's quite well with observations of phone batteries becoming problematic after ~3 years of daily charging.

Keep in mind that phone batteries, and laptop batteries, are generally charged to the top and then often completely exhausted. This is a worst case state-of-charge scenario for battery life, and doesn't happen in car batteries etc. For example, the Chevy Volt doesn't permit its battery to be charged over 80% or discharged less than 30%. GM expects its battery to drop only 10% after 5000 cycles.

Teslas do similar on the top-end. They don't normally charge past 80%. You can override this behavior in preparation for a long trip to ensure you have extra range available, but it reverts back to the default setting automatically after a few days.

> They don't normally charge past 80%.

I thought for Tesla it's 92% for a standard charge. The Volt is extremely conservative in this regard (Chevy was first out the gate).

As Lutz says in his book "Car guys vs. bean counters", that was done to make the Leaf battery last longer. The car industry knows that 80% of trips are under 40 miles, so most of the time, that's enough range. Longer, and they cut in the gasoline engine, so there's no reason to stress the battery life.

??? This was an entirely confused comment. (1) we are talking about SOC, not capacity, and (2) why are you talking about the Leaf?

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