Chevy Bolt EV Forum banner

61 - 74 of 74 Posts

·
Registered
Joined
·
1,071 Posts
I'm not assuming that 350 kW is the cap. In fact, we already know of 500+ kW systems that are being tested. My point is, the less often you have to go out of your way to refuel, the better, regardless of how long that stop takes. Ultimately, it's probably not going to be a choice. We're likely less than five years away from a 500+ mile, 500+ kW charging EV, and we're likely less than 10 years away from an affordable version of that EV.

My point, though, is that range is more important than charging speed, so if it was a choice, I'd rather have a 500-mile Bolt EV with 1 C charging rate than a 250-mile Bolt EV with a 3 C charging rate.
And I disagree 100%.

When you drove ICE cars exclusively (pre Volt) did you get a diesel truck with a dual fuel tank setup so you would only have to re-fuel once every 6 months? Or did you get an efficient car with a small fuel tank?

If you didn't get the diesel truck with the dual fuel tanks, then why do you want the EV equivelent today?

Keith
 

·
Registered
Joined
·
56 Posts
For the foreseeable future I will tend to agree with Eric. Perhaps because with an ICE vehicle fueling stops are consistently short, readily available, and require little (usually no) advance planning. Exactly the opposite of EVs. Hopefully that will continue to change.

Of course that little efficient gas car with a small tank still has significantly more range than out Bolts.
 

·
Registered
Joined
·
1,363 Posts
For the foreseeable future I will tend to agree with Eric. Perhaps because with an ICE vehicle fueling stops are consistently short, readily available, and require little (usually no) advance planning. Exactly the opposite of EVs. Hopefully that will continue to change.

Of course that little efficient gas car with a small tank still has significantly more range than out Bolts.
That's the $64,000 question. Two reinforce some other's sentiments, matching gas station build out is apples to pears, close but not quite. Very few ICEV drivers refuel at home. This BEV advantage covers probably 95% (WAG) of average BEV owners, especially non-Teslas. As the charging speeds hit 250kW at a minimum which I believe will be the case in the next few years, and the interstates become as congested with DCFC's to match the rest stop gas stations we now have (NYS Thruway as an example), stopping every 2 hours for 15 minutes will become the norm just like wearing masks in public is now. We adapt to what's reasonable and justified (or regulated) in our mind.
I'm not on board with the Moore's law theory that battery tech will double efficiency/power/range, at the same price every 18 months. It's just not happening. There will be incremental improvements such as what the Maxwell tech has shown with 300Wh/kg vs 246 Wh/kg in the current Model 3. This has been proven but the Model 3 has been in production for almost 3 years for a 20% improvement. That would get them to 400 miles which will probably be revealed at battery day next month est.
Now if they can get to the 500Wh/kg density, would be 200% increase to 600 miles. That would be an incredible improvement that seems a bit optimistic. I'll believe it when I see it.
Regardless, I still feel that the 400 mile range is the sweet spot for most especially considering the planned build out described above. There will still be >400 range vehicles available for specific use cases such as:
Cold climates
Commercial applications
Towing
Poor Aero
Rural areas
I'll try to dig up some stats on the breakdown of Model 3's by spec. LR, SR+, SR and we may see a surprising number feel that 250 mile range is adequate and the best value for a lot of people.
I would also suspect that the Chinese designed entry level Tesla will have <300 miles of range if it expects to hit <$25k price point regardless of Maxwell Magic.
 

·
Registered
Joined
·
4,551 Posts
I'm not on board with the Moore's law theory that battery tech will double efficiency/power/range, at the same price every 18 months. It's just not happening. There will be incremental improvements such as what the Maxwell tech has shown with 300Wh/kg vs 246 Wh/kg in the current Model 3. This has been proven but the Model 3 has been in production for almost 3 years for a 20% improvement.
Yeah, right now everyone is working on tweaks to existing Li-Ion technology, so improvements are slow but steady. What we really need is a breakthrough new technology, which everyone keeps promising but so far nobody has been able to deliver. There's a lot of money to be made from it, though, so I'd be surprised if something big doesn't happen within the next 10 years.
 

·
Registered
Joined
·
2,371 Posts
And I disagree 100%.

When you drove ICE cars exclusively (pre Volt) did you get a diesel truck with a dual fuel tank setup so you would only have to re-fuel once every 6 months? Or did you get an efficient car with a small fuel tank?

If you didn't get the diesel truck with the dual fuel tanks, then why do you want the EV equivelent today?

Keith
Actually, for a while, I did have a 300-gallon gas tank in my driveway (deliveries every couple of months), and my first F-350 did have 60 gallons of onboard fuel (a 20-gallon main tank and 40-gallon saddle tank).

Also, I think you're glossing over a few key factors. The first is financial. While it is possible to get a 20 mpg truck with two 20-gallon tanks (800 miles of range), it costs significantly more to drive than a 40 mpg car with a 13-gallon tank, which -- by the way -- still has 520 miles of range. In fact, it costs literally twice as much to drive.

The second factor is that ICE owners don't have a choice; they must go out of their way to fuel. It's something they tolerate, but would rather not do. Go survey as many ICE vehicle owners you know and ask them how much they look forward to stopping at a gas station. Note that I'm not talking about "stopping" during a trip (meals, restrooms, etc.), but specifically stopping at a gas station during the trip.

Essentially, even if you're someone who does want to stop every two hours of driving, a 500-mile EV wouldn't prevent you from doing that. However, what it would provide is the freedom to choose where and how long you stop.
 

·
Registered
Joined
·
2,371 Posts
Yeah, right now everyone is working on tweaks to existing Li-Ion technology, so improvements are slow but steady. What we really need is a breakthrough new technology, which everyone keeps promising but so far nobody has been able to deliver. There's a lot of money to be made from it, though, so I'd be surprised if something big doesn't happen within the next 10 years.
It depends whether you consider solid-state a "breakthrough new technology." Both GM and Samsung already have functioning solid-state cells with a pathway to 900-1,000 Wh/l energy density.

Otherwise, I think the most likely candidate is a reversible air-metal battery. The energy densities for aluminum and zinc air batteries is already ridiculously high, so now it's just a matter of figuring out how to rapidly reverse the reaction and put energy back into the battery.
 

·
Registered
Joined
·
447 Posts
And I disagree 100%.

When you drove ICE cars exclusively (pre Volt) did you get a diesel truck with a dual fuel tank setup so you would only have to re-fuel once every 6 months? Or did you get an efficient car with a small fuel tank?

If you didn't get the diesel truck with the dual fuel tanks, then why do you want the EV equivelent today?

Keith
I have to defend the opposite position here for a moment. There are a few differences between your analogy and reality. First is that instead of 160,000 gas stations there are only a few hundred charging stations. Second is that as evidenced on this forum often, reliability isn't is the same. Next there are several factors of difference in the fueling times. Finally even small fuel tank cars have several hundred miles of range even at 80+ MPH speeds.

Given all of that, wanting longer range does make some sense. The two problems I have with Eric's argument of bigger battery/slower charging is cost and efficiency. Any gains from making batteries cheaper are wiped out by making them bigger. And batteries are heavy. Eric is literally in the 0.1% range of highway drivers. Most everyone else commutes less than 50 miles a day and takes a small handful of very long trips per year. Carrying around those batteries 350 days a year just for the 10-15 long trip days really isn't all that efficient.

More charging stations with faster charging would give a better balance of cost and efficiency due to smaller, cheaper, lighter batteries.


ga2500ev
 

·
Registered
Joined
·
1,071 Posts
Renters in most cases can't charge at home... there is more resistance to that nation wide than in California, so good luck buying an EV in Mississippi if you don't have an understanding landlord or own your home. For people who can't charge at home, rapid charging is key.

As ICE cars are phased out, the choices are rapid charging everywhere, or relegation of "the little people" to disease ridden public transportation. Poor people are the ones most likely to be screwed over by the switch to renewable energy and the switch to EV's. The vast majority of us on this forum are financially sound and will suffer no ill effects, but you have to keep in mind that the majority of people are not as secure as we are.

Keith
 

·
Registered
Joined
·
2,371 Posts
I have to defend the opposite position here for a moment. There are a few differences between your analogy and reality. First is that instead of 160,000 gas stations there are only a few hundred charging stations. Second is that as evidenced on this forum often, reliability isn't is the same. Next there are several factors of difference in the fueling times. Finally even small fuel tank cars have several hundred miles of range even at 80+ MPH speeds.

Given all of that, wanting longer range does make some sense. The two problems I have with Eric's argument of bigger battery/slower charging is cost and efficiency. Any gains from making batteries cheaper are wiped out by making them bigger. And batteries are heavy. Eric is literally in the 0.1% range of highway drivers. Most everyone else commutes less than 50 miles a day and takes a small handful of very long trips per year. Carrying around those batteries 350 days a year just for the 10-15 long trip days really isn't all that efficient.

More charging stations with faster charging would give a better balance of cost and efficiency due to smaller, cheaper, lighter batteries.

ga2500ev
While I agree with your point about the increasing size of battery offsetting the cost savings, I think that's a concession we're going to have to continue making for awhile. It appears that the industry has settled on "affordable" EVs being $30,000 to $40,000. That means, we're likely to see ranges and battery sizes continue to increase while that ~$35,000 price point is preserved.

Where I disagree is with weight. As energy densities increase, it means that we will be able to preserve the weight of these EVs while increasing range. While the Bolt EV is a bit on the heavy side, it's actually not that much heavier than equivalent ICE vehicles with the same cargo capacity. Sure, it will be nice to have the option of reducing weight, but that's mostly an issue for performance vehicles. All other vehicles types would rather trade some weight capacity for range. Even EV trucks, where cargo weight capacity is a real selling point, really want to focus on range first.

To me, the strategy needs to be backward design. Essentially, setting the criteria/final standard, and then designing from there. For the short term, GM has stated that 300 miles is their minimum standard, and for trucks/luxury vehicles, it looks like they're setting their sites on 400+ miles. I think that's good. Essentially, what it means is achieve that baseline range standard, and then improve from there.

For me, whether people on this board or not agree, I think that 420 miles (yes, 420) is actually the range at which EVs will achieve mainstream adoption. In pleasant weather, that is enough range to cover the distance for most day trips. In winter, it will provide adequate driving range for a majority of Americans.
 

·
Registered
Joined
·
2,371 Posts
Renters in most cases can't charge at home... there is more resistance to that nation wide than in California, so good luck buying an EV in Mississippi if you don't have an understanding landlord or own your home. For people who can't charge at home, rapid charging is key.

As ICE cars are phased out, the choices are rapid charging everywhere, or relegation of "the little people" to disease ridden public transportation. Poor people are the ones most likely to be screwed over by the switch to renewable energy and the switch to EV's. The vast majority of us on this forum are financially sound and will suffer no ill effects, but you have to keep in mind that the majority of people are not as secure as we are.

Keith
Poor people are being screwed over either way. When half of Americans can't financially survive a $500 emergency, volatile gas prices can be devastating.

The one thing I would call out in your statement, though, is that even if rapid charging is the key to EV adoption (especially for those who are not financially stable), what makes us think that poorer communities will be adequately served? Electrify America actually had to completely rework their Cycle One plan in California due to backlash because they were largely ignoring under-served communities. If that doesn't also happen nationwide, it doesn't matter whether 200-mile EVs with rapid charging are widely available. People in poorer communities will continue to have no place to plug in.
 

·
Registered
2018 Bolt EV Premier Nightfall Gray
Joined
·
96 Posts
I'm not assuming that 350 kW is the cap. In fact, we already know of 500+ kW systems that are being tested. My point is, the less often you have to go out of your way to refuel, the better, regardless of how long that stop takes. Ultimately, it's probably not going to be a choice. We're likely less than five years away from a 500+ mile, 500+ kW charging EV, and we're likely less than 10 years away from an affordable version of that EV.

My point, though, is that range is more important than charging speed, so if it was a choice, I'd rather have a 500-mile Bolt EV with 1 C charging rate than a 250-mile Bolt EV with a 3 C charging rate.
Agreed. A 500-mile EV would cover a full day of driving for many of us, or may only require 1 short charge stop for heartier road-trippers.

At that point, overnight charging infrastructure would become a far more important factor for longer trips.
 

·
Registered
Joined
·
299 Posts
Agreed. A 500-mile EV would cover a full day of driving for many of us, or may only require 1 short charge stop for heartier road-trippers.

At that point, overnight charging infrastructure would become a far more important factor for longer trips.
That's the point where 32A L2 charging is going to start to be a nuisance. Filling a 120kWh battery is going to require longer than most overnight stays.
 

·
Registered
Joined
·
2,371 Posts
That's the point where 32A L2 charging is going to start to be a nuisance. Filling a 120kWh battery is going to require longer than most overnight stays.
I definitely think that the size of the L2 onboard charger needs to be scaled with the size of the battery. Personally, I think the goal should be 6 hours for a full charge on L2. The Bolt EV falls a bit short of that (it should have a 40 A onboard charger).

Of course, there will be a point where it's not possible. The SAE standard caps at 80 A, which would only be enough to maintain that 6-hour standard up to a 120 kWh battery size. Still, that would be fine for most average size cars, but it would fall short for what we expect for large EV SUVs and trucks.
 
61 - 74 of 74 Posts
Top