Have we reached a plateau in battery technology ?

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The question this discussion prompts then is: Will evolution of battery technology win the race against charge infrastructure expansion. ? The 200 mile battery might satisfy most single car owners. if 200 miles is the longest roundtrip distance that 95% of the drivers out there will traverse in one day, then remote charge stations will not get that much use for that type of owner, unless you want to take a long trip, which for most people, doesn't happen nearly as often. Where does that leave charge stations ?

I doubt it. I've mentioned this in a few other threads, but I'll mention it here too. I highly suspect that as the EV market grows, manufacturers will begin to offer vehicles with tiered battery sizes and prices. So yes, there might be a lot of EVs with 200 mile ranges, but there may also be a lot more with 50 mile ranges. Those smaller ranges will be key to reducing the cost enough to penetrate that price-point that will appeal to the masses. And being 50 mile range will be adequate for most daily commutes, charging stations will help with those longer commutes. I've been told the Leaf's battery costs $18,000 currently. So using half of that battery should cost around $9,000. So that would put the price of a Leaf down to $23,000 instead of $32,000. And once all of the tax incentives go away, that will be an important price point to reach. And of course those with deeper pockets can opt for the larger battery.

Of course I could be totally wrong on this. The only thing that I believe will keep this scenario from happening is if they can drastically reduce the cost of the batteries. In which case all EVs will have long ranges. But if battery costs remain the same for the next 5 to 10 years, then putting a smaller battery will be the only way to go to bring the cost down.

And I have to wonder how far you might be able to go by taking a battery half the size of a Leaf's battery and putting it in a car the size of a Honda CR-Z.

And lets not forget PHEVs. I imagine as long as the price is decent, even owners of Chevy Volts and other PHEVs will opt to charge at a public charger if it means they can make it home without paying for gas.

 

[DaveEV]

They cant add more series modules because the voltage would get too high

Voltage isn't too high. All of Toyota's recent hybrids boost the hybrid pack voltage up to 650V DC when needed. The LEAF's pack is a ways from that, so they could easily boost voltage by 25% without issue.

Nissan could also do the same thing that Toyota is doing and actually switch modules in/out as they become spent, that might not be a bad way to do it.

Toyota isn't doing that with any production vehicles. That was only done for the Prius PHEV prototypes which used 3 NiMH batteries.

 

[Herm]

Recent report stated they are still doing that , but with four battery sections instead of three, in the new Toyota PIP.. the one that uses lithium. We need to be careful on the PIP, they made 600 or 800 "prototypes" and had them all over the place for a long time, lots of media articles based on those cars.

Good point on the 650v Prius inverter, so there is still some room to increase voltage. Motor rpm (above 10k rpm) would go up so you would have to change the gearing.

 

[jkirkebo]

They cant add more series modules because the voltage would get too high

Voltage isn't too high. All of Toyota's recent hybrids boost the hybrid pack voltage up to 650V DC when needed. The LEAF's pack is a ways from that, so they could easily boost voltage by 25% without issue.

You can't have a battery voltage above 500V and still use the DC Fast Chargers. They are limited to 500V maximum, that would suggest about 450V nominal battery voltage is the limit.

 

[DaveEV]

Recent report stated they are still doing that , but with four battery sections instead of three, in the new Toyota PIP.. the one that uses lithium.

References?

You can't have a battery voltage above 500V and still use the DC Fast Chargers. They are limited to 500V maximum, that would suggest about 450V nominal battery voltage is the limit.

Hmm... good point. I wonder why they didn't go with 600V maximum as 600V is a common maximum voltage in the electrical world...

 

[Yodrak]

Excellent point about daily usage. And I agree that with a larger battery capacity they would reasonably provide a higher charge rate to avoid extending the charging time any more than necessary.

If it takes 6-7 hours to charge our current system (on 220V system), does that mean it will take at least 14 hours (charge cycle is non-linear) to fully charge a "200 mile" battery ?

It does unless the charging current is increased, yes. If the energy capacity of the battery increases, but the energy delivery rate remains the same, it will take longer to fill the battery.

All quite true, but you are asking the wrong question. Will your daily mileage double just because you have a 200 mile battery? I think most people on this board are finding that the current range is adequate for their daily requirement. Where we want the extra range is for the occasional longer trip; the one for which we currently have to revert to our dinosaur car.

If I am right, and I know I am for my personal situation, it follows that the daily charge time would not increase even if the delivery rate remains the same. We would only have to plan ahead a bit more for the longer trips.

Actually, of course, it doesn't look like it will be a problem at all. Most people have a charging dock which can already handle twice the current that the LEAF can pull. And I can almost guarantee that a LEAF with a 200 mile battery will have at least the faster 6.6kW charger that Ford is coming out with next year and Nissan will "probably" make standard a year later. The only people pinched at all, other than those charging on 120v, are those like me who currently have 12A or 16A EVSEs, and as I just said, I don't see it as a problem. Anyone who does (including the 120v folks) can simply upgrade to a faster EVSE.

The bottom line is that your charging time won't double, in fact it will be cut in half most days!

Ray