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Comment by slashdotdash | Hacker News Reader

Vehicle to grid may actually improve battery health and keep them healthier for longer.

> “This new research into the potentials of V2G shows that it could actually improve vehicle battery life by around ten percent over a year.”

This requires intelligent usage where the battery state of charge is kept within a limited window, not fully charged or drained.

[1] https://warwick.ac.uk/newsandevents/pressreleases/clean_ener...

[2] https://www.sciencedirect.com/science/article/pii/S036054421...

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As I read this, it's basically saying that a battery used for V2G power would spent more time at a lower state of charge which doesn't degrade the battery as fast, to such a degree that this factor outweighs the extra cycles on the pack? Seems like an extraordinary claim - I'd want to see it demonstrated experimentally and not just assumed based on a model (no matter how many times they say the model is 'verified').

They did run an experiment on actual batteries. It's still only one kind of cell, but they have actual experimental evidence:

https://ars.els-cdn.com/content/image/1-s2.0-S03605442173068...

I don’t think reducing the effective range of your car to preserve battery life will be very popular; people want the freedom to drive as far as they can, because it’s hard to predict when they will need that capability, and charging is very slow. If someone does have a very predictable routine they can just not overcharge their car in the first place and save the discharge wear.

> people want the freedom to drive as far as they can, because it’s hard to predict when they will need that capability, and charging is very slow

For most people, if they really need to drive hundreds of miles unexpectedly, I doubt spending 15 minutes at a high-speed charger to top up the batteries will be an issue.

As someone who drives an EV, I can tell you that it’s not the long distance trips, it’s having an unexpectedly busy day of errands in cold weather that gets you—realizing that you’re starting out at only 50% charge, which means you can’t make that last trip into the suburbs at the end of the day. There are very few fast chargers in densely populated areas and they’re often malfunctioning, or have queues. They also hurt your battery, so not to be used on a regular basis.

In Norway where chargers are a lot more common, it's not an issue. Of course if I want to charge at 4pm at a popular place it may be a queue but most of the times many chargers are available and functional.

> There are very few fast chargers in densely populated areas

I live in Norway so not a huge issue, and I expect it to get better. Circle K for example is pushing hard to build high-speed chargers at their stations.

That's one use case of car driving, yes, but most people have a fixed daily / weekly routine.

Plus it could be a setting, where people can tell the car to top it up overnight instead of optimize for battery life.

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