4 ms·

I haven’t heard of this effect. What is the timeline of degradation from just chronological aging?

philipkglass 3y ago
I don't know if ProllyInfamous is correct about electric vehicle batteries degrading more from age than from cycling, but it is an effect that shows up in batteries. The terms to describe the effects are "cycle life" and "calendar life." Increasing calendar age can degrade batteries that just sit there without deliberate charge or discharge processes. An example would be an old package of Duracell batteries, never used, that sat in the closet for decades and lost power before they ever went into a remote control. Those batteries reached the end of their calendar life.
- nostrademons 3y ago
  Also note that this affects battery chemistries other than lithium as well. My (lead-acid) car battery is currently dead. The battery itself is 7 years old. The previous battery died at 8 years old. The service tech at the last replacement said that's pretty typical, and (ICE) car batteries are usually slated to be replaced at the 8-year mark.
PaulKeeble 3y ago
The manufacturers certainly list it as part of the expected life. Lipo batteries for example are guaranteed for 6000 cycles at which point they will have 80% of their rated capacity and a minimum of 10 years. So they are fairly certain one of those two criteria is going to lead to the battery no longer meeting >80% capacity. But that is the other thing about them only lasting 6k cycles or 10 years, its not like the battery is expected to be dead just lacking a fifth of its capacity. What is happening with batteries out of old EVs today is either cell scavenging and remade into new batteries or just racking the whole battery into grid storage. Per KWH they pretty cheap once they are that degraded but still quite usable in other applications.
- anonuser123456 3y ago
  This is depressing. I had never really considered chronological age when looking at batteries. The longevity is really important for the ultimate economic viability and I’ve been tracking that to decide when to pull the trigger on a home battery. A 6000 or 10 year cycle rating means functionally 10 years for a solar deployment because you are only cycling the batteries 1x per day. I was hoping you could get 20 years out of such a system (thus halving the cost). Bummer.
  - ProllyInfamous 3y ago
    Unless you live in California, and use a "time of day" meter [for kWH offsetting], there are few reasons you would need at-home battery storage (other than power outages... get a gasoline generator, instead!). Direct-tie inverters utilize "the electric grid" as your battery/capacitor... unless you are off the grid. Also, there is a glaring safety defect that violates UL, contained within every Tesla Powerwall 2... so don't get one of those.

I don't know if ProllyInfamous is correct about electric vehicle batteries degrading more from age than from cycling, but it is an effect that shows up in batteries. The terms to describe the effects are "cycle life" and "calendar life." Increasing calendar age can degrade batteries that just sit there without deliberate charge or discharge processes. An example would be an old package of Duracell batteries, never used, that sat in the closet for decades and lost power before they ever went into a remote control. Those batteries reached the end of their calendar life.

nostrademons 3y ago
Also note that this affects battery chemistries other than lithium as well. My (lead-acid) car battery is currently dead. The battery itself is 7 years old. The previous battery died at 8 years old. The service tech at the last replacement said that's pretty typical, and (ICE) car batteries are usually slated to be replaced at the 8-year mark.

PaulKeeble 3y ago

The manufacturers certainly list it as part of the expected life. Lipo batteries for example are guaranteed for 6000 cycles at which point they will have 80% of their rated capacity and a minimum of 10 years. So they are fairly certain one of those two criteria is going to lead to the battery no longer meeting >80% capacity. But that is the other thing about them only lasting 6k cycles or 10 years, its not like the battery is expected to be dead just lacking a fifth of its capacity. What is happening with batteries out of old EVs today is either cell scavenging and remade into new batteries or just racking the whole battery into grid storage. Per KWH they pretty cheap once they are that degraded but still quite usable in other applications.

anonuser123456 3y ago
This is depressing. I had never really considered chronological age when looking at batteries. The longevity is really important for the ultimate economic viability and I’ve been tracking that to decide when to pull the trigger on a home battery. A 6000 or 10 year cycle rating means functionally 10 years for a solar deployment because you are only cycling the batteries 1x per day. I was hoping you could get 20 years out of such a system (thus halving the cost). Bummer.
- ProllyInfamous 3y ago
  Unless you live in California, and use a "time of day" meter [for kWH offsetting], there are few reasons you would need at-home battery storage (other than power outages... get a gasoline generator, instead!). Direct-tie inverters utilize "the electric grid" as your battery/capacitor... unless you are off the grid. Also, there is a glaring safety defect that violates UL, contained within every Tesla Powerwall 2... so don't get one of those.