Will Electric Vehicles Be Viable? When?

[Tommy Cookers]

in a way the range reduction is built-in from day 1
(to make the battery warranty hold up the car is arranged normally to use only about 35% of its full capacity ie range)

presumably if there is now improved battery life this would appear (already ?) as some of .....

75%-85% is closer to what I've found. Anything I have tested is charged to 85% as new and increased to 100% over the life of the battery (your chemistry may vary) . Maybe less would be more fruitful but it would also limit the range when new to the point of effecting the products utility. In a car this may be easier to accomplish but on a bike it really does ad significant weight if i'm assuming packaging 50% more battery, especially considering the battery is swap-able. I have never heard of a battery being used at 35% state of charge, but I do know most oem's have very specific charging cycles which maximize both range and reliability against charging cycles.

getting 6 or 7 years warranty by (covertly) limiting the (working) range to the 35% capacity between 35% and 70 %
(not the 35% between 0% and 35%)
nothing bad about this of course

no they wouldn't size an electric bicycle battery (or electric 'plane battery) that way
lead/acid battery bikes were advertised as 200 - 300 cycle life - and lithium battery ones as 1000 cycle life

[joshuagore]

in a way the range reduction is built-in from day 1
(to make the battery warranty hold up the car is arranged normally to use only about 35% of its full capacity ie range)

presumably if there is now improved battery life this would appear (already ?) as some of .....

75%-85% is closer to what I've found. Anything I have tested is charged to 85% as new and increased to 100% over the life of the battery (your chemistry may vary) . Maybe less would be more fruitful but it would also limit the range when new to the point of effecting the products utility. In a car this may be easier to accomplish but on a bike it really does ad significant weight if i'm assuming packaging 50% more battery, especially considering the battery is swap-able. I have never heard of a battery being used at 35% state of charge, but I do know most oem's have very specific charging cycles which maximize both range and reliability against charging cycles.

getting 6 or 7 years warranty by (covertly) limiting the (working) range to the 35% capacity between 35% and 70 %
(not the 35% between 0% and 35%)
nothing bad about this of course

no they wouldn't size an electric bicycle battery (or electric 'plane battery) that way
lead/acid battery bikes were advertised as 200 - 300 cycle life - and lithium battery ones as 1000 cycle life

I just misunderstood completely, probably the time of night I responded. I don't drain to 0% either, and yes I would love to get 1000 cycles out of our batteries. That would be a treat, im looking at less but also have a less capable battery management system, I can imagine the big boys have some pretty slicks stuff going on.

[Big Tea]

75%-85% is closer to what I've found. Anything I have tested is charged to 85% as new and increased to 100% over the life of the battery (your chemistry may vary) . Maybe less would be more fruitful but it would also limit the range when new to the point of effecting the products utility. In a car this may be easier to accomplish but on a bike it really does ad significant weight if i'm assuming packaging 50% more battery, especially considering the battery is swap-able. I have never heard of a battery being used at 35% state of charge, but I do know most oem's have very specific charging cycles which maximize both range and reliability against charging cycles.

getting 6 or 7 years warranty by (covertly) limiting the (working) range to the 35% capacity between 35% and 70 %
(not the 35% between 0% and 35%)
nothing bad about this of course

no they wouldn't size an electric bicycle battery (or electric 'plane battery) that way
lead/acid battery bikes were advertised as 200 - 300 cycle life - and lithium battery ones as 1000 cycle life

I just misunderstood completely, probably the time of night I responded. I don't drain to 0% either, and yes I would love to get 1000 cycles out of our batteries. That would be a treat, im looking at less but also have a less capable battery management system, I can imagine the big boys have some pretty slicks stuff going on.

This is another weak point of EV's. Not only is the range quite low to start with, but because of this the natural thing is to 'keep it topped up' rather than running it full (recommended) cycles. So what would only really need to be a weekly charge can easily become a day by day charge.

[Just_a_fan]

This is another weak point of EV's. Not only is the range quite low to start with, but because of this the natural thing is to 'keep it topped up' rather than running it full (recommended) cycles. So what would only really need to be a weekly charge can easily become a day by day charge.

Can be easily dealt with by using lots of cells and ensuring that each is charged/discharged in the best way. It would be transparent to the user - they'd just see a single battery charge status rather than 100 little charge statuses but the battery controller would be keeping each cell in its happy place.

[Big Tea]

This is another weak point of EV's. Not only is the range quite low to start with, but because of this the natural thing is to 'keep it topped up' rather than running it full (recommended) cycles. So what would only really need to be a weekly charge can easily become a day by day charge.

Can be easily dealt with by using lots of cells and ensuring that each is charged/discharged in the best way. It would be transparent to the user - they'd just see a single battery charge status rather than 100 little charge statuses but the battery controller would be keeping each cell in its happy place.

As in a SolidState Hard Drive? Yes. But what I mean is that if a range is small, the spare capacity becomes less. For instance, charge on Sunday to a range of 200 miles, use Monday, Tuesday and Wednesday at 20 miles there 20 back and the remaining range is 140. If (say) parents live 50 miles away that is it. No spare capacity for unforseen little trips, so you charge it Wednesday 'incase', thus charging twice as often as really required, 104 a year instead of 52.

[henry]

in a way the range reduction is built-in from day 1
(to make the battery warranty hold up the car is arranged normally to use only about 35% of its full capacity ie range)

presumably if there is now improved battery life this would appear (already ?) as some of .....

75%-85% is closer to what I've found. Anything I have tested is charged to 85% as new and increased to 100% over the life of the battery (your chemistry may vary) . Maybe less would be more fruitful but it would also limit the range when new to the point of effecting the products utility. In a car this may be easier to accomplish but on a bike it really does ad significant weight if i'm assuming packaging 50% more battery, especially considering the battery is swap-able. I have never heard of a battery being used at 35% state of charge, but I do know most oem's have very specific charging cycles which maximize both range and reliability against charging cycles.

getting 6 or 7 years warranty by (covertly) limiting the (working) range to the 35% capacity between 35% and 70 %
(not the 35% between 0% and 35%)
nothing bad about this of course

no they wouldn't size an electric bicycle battery (or electric 'plane battery) that way
lead/acid battery bikes were advertised as 200 - 300 cycle life - and lithium battery ones as 1000 cycle life

How does this manifest itself? Do they fit larger batteries but only use part? Or do they advertise a capacity, and hence range, but never allow the user to charge fully and tell them they are out of charge when there’s lots left?

[Just_a_fan]

This is another weak point of EV's. Not only is the range quite low to start with, but because of this the natural thing is to 'keep it topped up' rather than running it full (recommended) cycles. So what would only really need to be a weekly charge can easily become a day by day charge.

Can be easily dealt with by using lots of cells and ensuring that each is charged/discharged in the best way. It would be transparent to the user - they'd just see a single battery charge status rather than 100 little charge statuses but the battery controller would be keeping each cell in its happy place.

As in a SolidState Hard Drive? Yes. But what I mean is that if a range is small, the spare capacity becomes less. For instance, charge on Sunday to a range of 200 miles, use Monday, Tuesday and Wednesday at 20 miles there 20 back and the remaining range is 140. If (say) parents live 50 miles away that is it. No spare capacity for unforseen little trips, so you charge it Wednesday 'incase', thus charging twice as often as really required, 104 a year instead of 52.

No doubt this will a problem initially if it's an only car. For those who have more than one car, I would think it'll be ok. Also, once batteries improve and people get the feel for them, it'll be increasingly less problematic.

[joshuagore]

75%-85% is closer to what I've found. Anything I have tested is charged to 85% as new and increased to 100% over the life of the battery (your chemistry may vary) . Maybe less would be more fruitful but it would also limit the range when new to the point of effecting the products utility. In a car this may be easier to accomplish but on a bike it really does ad significant weight if i'm assuming packaging 50% more battery, especially considering the battery is swap-able. I have never heard of a battery being used at 35% state of charge, but I do know most oem's have very specific charging cycles which maximize both range and reliability against charging cycles.

getting 6 or 7 years warranty by (covertly) limiting the (working) range to the 35% capacity between 35% and 70 %
(not the 35% between 0% and 35%)
nothing bad about this of course

no they wouldn't size an electric bicycle battery (or electric 'plane battery) that way
lead/acid battery bikes were advertised as 200 - 300 cycle life - and lithium battery ones as 1000 cycle life

How does this manifest itself? Do they fit larger batteries but only use part? Or do they advertise a capacity, and hence range, but never allow the user to charge fully and tell them they are out of charge when there’s lots left?

If I am building a 1.2kw battery, it may have 1.5kw worth of cells, charged to 80% and over the life of the battery the state of charge can be increased to 90%, or more, this assumes the user expects a 5-8+ year lifespan. If the customers expectations are 2-3 years lifespan then maybe choices are different (who wants to carry around extra cells on an ultralight package i.e. plane/cabron fiber bike). This is pretty rudimentary compared to tesla or what others may do.

I have found that lower states of charge also play nicer with the battery management systems. The bms measures the cell voltages, logs capacity, load, and temperature and besides transferring high voltage cell power to low voltage cells, you can tune minimum/max draw in ah and thermal rollback all through bluetooth.

Here is a prototype 1.2kw battery. Mistakes were made in this configuration, so changes will be made.


Here is my information dump on battery charging etc..
https://survey.pluginamerica.org/tesla- ... -Study.pdf
https://www.mdpi.com/2076-3417/8/10/1825
http://css.umich.edu/sites/default/file ... S20-08.pdf
https://energy.stanford.edu/sites/g/fil ... 3cf657.pdf
https://www.nature.com/articles/s41598-019-51474-5

[Tommy Cookers]

getting 6 or 7 years warranty by (covertly) limiting the (working) range to the 35% capacity between 35% and 70 %
(not the 35% between 0% and 35%)
nothing bad about this of course

....Do they fit larger batteries but only use part? Or do they advertise a capacity, and hence range, but never allow the user to charge fully and tell them they are out of charge when there’s lots left?

yes to both - afaik

this is what was done with the Prius (giving an 8 year warranty) - and equivalent products presumably
I assume the BEVs do something similar
eg hasn't there been a button to press for emergency range extension ? (use of which is severely limited by the warranty)

regardless - the battery 'is what it is'

[Andres125sx]

Maybe it's not common in Europe but long road trips are part of the driving cultures in the US and Australia. We drive from Melbourne to Adelaide (~800 k's each way) and Melbourne to the Central Coast of NSW (~950k's each way) once each year to visit family on our Holidays. When I lived in Sydney I used to drive 1,400k's to Adelaide (each way twice a year). This is fairly normal here - Australia is a vast country. It's literally 95% the size of the USA - you could fit all of the European landmasses in Australia and still not match our vast country.

https://takrawesome.com/wp-content/uplo ... europe.jpg

I agree with you that Charge time is the real issue - but only for long road trips, for day to day imo it's a non-issue for most ppl who can charge at home.

The key here is what I highlighted, once or twice a year

True but 2,500+ k's of road trip driving per year is still getting close to 20% of our average yearly total of 15,000 k's driven for that vehicle.

Yes but not sure what you mean with this. It´s 20% of total mileage but only for those who made those long trips, not the real average.

It´s also showing how many mileage you´d save to your own car, increasing its lifespan, reducing maintenance costs, and making this combination more sensible. It would also make your own car choice more appropiate to the daily use it will do 80% of the time, so it´s all advantages

[Andres125sx]

getting 6 or 7 years warranty by (covertly) limiting the (working) range to the 35% capacity between 35% and 70 %
(not the 35% between 0% and 35%)
nothing bad about this of course

no they wouldn't size an electric bicycle battery (or electric 'plane battery) that way
lead/acid battery bikes were advertised as 200 - 300 cycle life - and lithium battery ones as 1000 cycle life

I just misunderstood completely, probably the time of night I responded. I don't drain to 0% either, and yes I would love to get 1000 cycles out of our batteries. That would be a treat, im looking at less but also have a less capable battery management system, I can imagine the big boys have some pretty slicks stuff going on.

This is another weak point of EV's. Not only is the range quite low to start with, but because of this the natural thing is to 'keep it topped up' rather than running it full (recommended) cycles. So what would only really need to be a weekly charge can easily become a day by day charge.

Lithium batteries are NOT recommended to run full cycles, but the opposite. That was the recommendation for previous Nixx batteries, wich have memory effect so full cycles were recommended to keep the full capacity.

But with lithium batteries it´s the opposite. If you´re going to use 80% of the capacity during 4 days, for the battery it is much better to charge a 20% each day, keeping battery level between 50-70%, than charging one day and using from 100% to 20%. Both are considered 0.8 cycles btw, it doesn´t matter if charging that 80% is done at once or during 4 days, something I leart a few days ago. But charging a 20% each day will increase the total cycles of the battery, or to be more precise, it will not reduce cycle life, while using the battery from 100% to 20% will.

[Andres125sx]

The thread seems To have drifted from when will BEVs be viable to when will they be mainstream.

True, but for obvious reasons, they´re viable today, even if not for 100% of people, but that´s true for any car...

For example, are american trucks viable? For me they are not, I don´t need 4x4 capabilities, I don´t need anything that big and it would actually be a big problem when I have to park at any street , and I´m not going to pay all the fuel they waste due to their weight and engine size, so they´re not viable for me, like they aren´t for a lot of people. But that does not prevent manufacturers to sell some thousands each year.

Same for EVs, even if they´re not viable for everybody, they are for many people, so the only question remaining is when they will become mainstream

[Andres125sx]

in a way the range reduction is built-in from day 1
(to make the battery warranty hold up the car is arranged normally to use only about 35% of its full capacity ie range)

presumably if there is now improved battery life this would appear (already ?) as some of .....
increased warranty life
increased range
range/life unincreased but battery cost/weight reduced

75%-85% is closer to what I've found. Anything I have tested is charged to 85% as new and increased to 100% over the life of the battery (your chemistry may vary) . Maybe less would be more fruitful but it would also limit the range when new to the point of effecting the products utility. In a car this may be easier to accomplish but on a bike it really does ad significant weight if i'm assuming packaging 50% more battery, especially considering the battery is swap-able. I have never heard of a battery being used at 35% state of charge, but I do know most oem's have very specific charging cycles which maximize both range and reliability against charging cycles.

Let me see if I got this right. You mean that when an EV is sold, the battery is used maybe from 35% to 85% wich provides the advertised range, but year by year that margin is increased, using the battery from 32 to 87% after some time of use, 30-90% some years later, and at some point battery is used from 0-100%, so battery capacity reduction due to age is compensated and the EV keep a similar range during all its lifespan?

That´s interesting

[strad]

Same for EVs, even if they´re not viable for everybody, they are for many people, so the only question remaining is when they will become mainstream

I think that is right Andres and I think I should have named the thread :When Will Electric Vehicles Become Mainstream.
I'm not sure your average consumer will quite grasp all this battery stuff you guys have been talking about.
They don't want to have to worry about amounts of charging they just want to charge them and drive them.

[Big Tea]

I just misunderstood completely, probably the time of night I responded. I don't drain to 0% either, and yes I would love to get 1000 cycles out of our batteries. That would be a treat, im looking at less but also have a less capable battery management system, I can imagine the big boys have some pretty slicks stuff going on.

This is another weak point of EV's. Not only is the range quite low to start with, but because of this the natural thing is to 'keep it topped up' rather than running it full (recommended) cycles. So what would only really need to be a weekly charge can easily become a day by day charge.

Lithium batteries are NOT recommended to run full cycles, but the opposite. That was the recommendation for previous Nixx batteries, wich have memory effect so full cycles were recommended to keep the full capacity.

But with lithium batteries it´s the opposite. If you´re going to use 80% of the capacity during 4 days, for the battery it is much better to charge a 20% each day, keeping battery level between 50-70%, than charging one day and using from 100% to 20%. Both are considered 0.8 cycles btw, it doesn´t matter if charging that 80% is done at once or during 4 days, something I leart a few days ago. But charging a 20% each day will increase the total cycles of the battery, or to be more precise, it will not reduce cycle life, while using the battery from 100% to 20% will.

I mean more due to the compounding effect on not having a longer range, and when 'unforeseen' events do turn up, it is often the very time you can not afford to take 6 hours or what ever needed to give yourself the charge.
This may not be the truth of it, and it may happen less than birthdays, but it will still be in mind. 5min at a fuel station can be disregarded, but if you need to be somewhere NOW it becomes a disproportionate concern.