4 ms·

Exactly right. 5478 cycles at 200 miles per is greater than 1,000,000 miles. Few people will put that many miles on a car. OTOH, given how there are fewer mov

Exactly right. 5478 cycles at 200 miles per is greater than 1,000,000 miles. Few people will put that many miles on a car. OTOH, given how there are fewer moving parts in EVs, there's certainly a better chance for an EV to make it the distance than for an IC car.

dade_ 9y ago
Automated driving / assisted driving may also reduce the odds of a car being totalled. It will be interesting to see the stats.
chongli 9y ago
Batteries don't maintain their maximum charge cycle to cycle. High cycle count batteries hold a fraction of the charge of new batteries. You may get 200 per cycle at the beginning but after a few hundred cycles that could drop down to 150. Depending on your daily commute, the car may become unusable long before the battery is completely exhausted.
- Robotbeat 9y ago
  Usually the "cycle life" of a battery is when the capacity drops to 80% of new when fully discharged and recharged. You can extend the life of most lithium batteries dramatically by not charging all the way and not discharging all the way. Use the middle 50% of the battery's capacity for the vast majority of the cycles, and your battery may last 4 times as many cycles.
  - chongli 9y ago
    But that means your 200 mile battery is now a 100 mile battery from day one. If your daily commute is 150 miles, that means you need to carry the weight of a 300 mile battery. With all the extra expense of moving the additional weight plus the extra initial cost of the larger battery, are you really further ahead?
    - kwhitefoot 9y ago
      If your daily commute is 150 miles perhaps you are living or working in the wrong place. :-) Of course if you have access to electricity at your workplace you only need 75 miles anyway. A Hyundai Ioniq charging from a normal 230V 16A circuit charges fully in about 8 hours giving you about 150 miles. But 75 miles to get there means it will be only half empty when you arrive so it will only take 4 hours. The real challenges with electric cars now for the near and medium future are infrastructure not range. There is a project starting, in the UK I think, to turn lamp posts in to charging stations. One could imagine a scenario where companies used the availability of charging stations in company car parks as incentives to work there.
      - Robotbeat 9y ago
        Range helps address infrastructure by not needing as many charging stations. Since EV owners typically charge every night, that means only trips that last over 200 miles need any kind of public charging infrastructure at all. Also, if evenly spaced over an area, you need only a quarter as many charging stations as you do with 100 mile range (besides the above effect of having to do fewer trips that require charging stations to begin with). And with a larger battery, the vehicle can accept a much higher rate of charge. That's partly why 75-100kWh Teslas can do 120kW Supercharging and 30kWh Nissan Leafs can only do 44kW DC fast charging at most.
    - Robotbeat 9y ago
      No it doesn't. It means you just charge it to 150 mile range then make sure you charge it before you get down to 50 miles unless you take a long trip. Not a problem if you charge at home every night like most EV owners do (like a cell phone). Most gas car users probably operate in a similar manner already except they don't have the advantage of being able to charge up conveniently at home. You still have the extra range for longer trips or for contingency, of course. Other advantages of a large battery: The battery can discharge at a higher power and with more efficiency for the same power. Same for charging. And yeah, even with the extra weight, you're far ahead. Big battery is the way to go. Charge it like I've described, and the battery will last for 200,000 miles, probably more. And remember, because you have a big battery, you also can tolerate a LOT more battery degradation. If you have a 200 mile battery initially but only need 100 miles of range, then you might be able to drive the thing, say, 500,000 or more miles before you run against that 100 mile range requirement.

dade_ 9y ago

Automated driving / assisted driving may also reduce the odds of a car being totalled. It will be interesting to see the stats.

chongli 9y ago

Batteries don't maintain their maximum charge cycle to cycle. High cycle count batteries hold a fraction of the charge of new batteries. You may get 200 per cycle at the beginning but after a few hundred cycles that could drop down to 150. Depending on your daily commute, the car may become unusable long before the battery is completely exhausted.

Robotbeat 9y ago
Usually the "cycle life" of a battery is when the capacity drops to 80% of new when fully discharged and recharged. You can extend the life of most lithium batteries dramatically by not charging all the way and not discharging all the way. Use the middle 50% of the battery's capacity for the vast majority of the cycles, and your battery may last 4 times as many cycles.
- chongli 9y ago
  But that means your 200 mile battery is now a 100 mile battery from day one. If your daily commute is 150 miles, that means you need to carry the weight of a 300 mile battery. With all the extra expense of moving the additional weight plus the extra initial cost of the larger battery, are you really further ahead?
  - kwhitefoot 9y ago
    If your daily commute is 150 miles perhaps you are living or working in the wrong place. :-) Of course if you have access to electricity at your workplace you only need 75 miles anyway. A Hyundai Ioniq charging from a normal 230V 16A circuit charges fully in about 8 hours giving you about 150 miles. But 75 miles to get there means it will be only half empty when you arrive so it will only take 4 hours. The real challenges with electric cars now for the near and medium future are infrastructure not range. There is a project starting, in the UK I think, to turn lamp posts in to charging stations. One could imagine a scenario where companies used the availability of charging stations in company car parks as incentives to work there.
    - Robotbeat 9y ago
      Range helps address infrastructure by not needing as many charging stations. Since EV owners typically charge every night, that means only trips that last over 200 miles need any kind of public charging infrastructure at all. Also, if evenly spaced over an area, you need only a quarter as many charging stations as you do with 100 mile range (besides the above effect of having to do fewer trips that require charging stations to begin with). And with a larger battery, the vehicle can accept a much higher rate of charge. That's partly why 75-100kWh Teslas can do 120kW Supercharging and 30kWh Nissan Leafs can only do 44kW DC fast charging at most.
  - Robotbeat 9y ago
    No it doesn't. It means you just charge it to 150 mile range then make sure you charge it before you get down to 50 miles unless you take a long trip. Not a problem if you charge at home every night like most EV owners do (like a cell phone). Most gas car users probably operate in a similar manner already except they don't have the advantage of being able to charge up conveniently at home. You still have the extra range for longer trips or for contingency, of course. Other advantages of a large battery: The battery can discharge at a higher power and with more efficiency for the same power. Same for charging. And yeah, even with the extra weight, you're far ahead. Big battery is the way to go. Charge it like I've described, and the battery will last for 200,000 miles, probably more. And remember, because you have a big battery, you also can tolerate a LOT more battery degradation. If you have a 200 mile battery initially but only need 100 miles of range, then you might be able to drive the thing, say, 500,000 or more miles before you run against that 100 mile range requirement.