Remote Electric Vehicle Charging

[scottnichol]

I’m considering my next vehicle choice and something like a Kia EV6 is in the running. Given that this is an all electric vehicle, I’m of course thinking about charging on the go and wondering if it’s possible to design a portable system that could be deployed while remote and not near a charger. For instance, while camping or doing some other outdoor activities.

Level 2 EV charging requires 240V and about 40A. Is it possible to deliver that in a smallish, portable system that could be easily deployed while the vehicle is parked?

If you have any experience with something like this, please share!

 

[HRTKD]

If you build a 220 volt system then it's possible. But then that system cannot be used for 110 volt loads.

My 2015 Leaf came with an EVSE that could run on either 110 or 220. It would run on a standard 15 amp house circuit. I typically used it on a 220v 30 amp circuit. The 2019 Leaf came with an EVSE draws more amps. It would trip the 30 amp amp 220 volt breaker every time. I kept the 2015 EVSE and it does work on the 2019. I don't know if that option is available to you or not.

The downside of the 110 volt circuit is that it takes f-o-r-e-v-e-r to charge the EV battery. I charged my EV from my RV trailer's system to stress test the RV system, looking for hot spots. That ran for three hours, taking the 560 Ah battery bank from 100% down to ~39%. The PV system was providing about 500 watts most of the time.

To make a long post even longer, it takes a substantial system to charge an EV. If you can put in a hefty 220 volt inverter that is fed by lots and lots of PV, it could work. Keep in mind that the inverter is going to generate a lot of heat and you need to deal with that.

 

[ChrisG]

I’m considering my next vehicle choice and something like a Kia EV6 is in the running. Given that this is an all electric vehicle, I’m of course thinking about charging on the go and wondering if it’s possible to design a portable system that could be deployed while remote and not near a charger. For instance, while camping or doing some other outdoor activities.

Level 2 EV charging requires 240V and about 40A. Is it possible to deliver that in a smallish, portable system that could be easily deployed while the vehicle is parked?

If you have any experience with something like this, please share!

240v at 40a is 9600w. That would require at least 25 400w panels at 50 lbs each, so no way that’s portable. I’ve seen videos of L1 charging off of a EcoFlow, but it was pre charged and can only support a few mile emergency use only.

 

[rustythorn]

a "small" system could be either a ecoflow or bluetti dual setup with their respective split phase adapters, you could get up to 24kwh of charging that way and it would be modular. the bluetti is a little better here because it can power 120v and 240v simultaneously

for a bigger system you can pick from a wide variety of inverters or all in one systems. the advantage of all in one [split phase] systems will allow both 120v and 240v simultaneously but all that i know of require 240 grid input. you could get a transformer to buck up 120. this would allow you to translate a level one charging [120v] to level two [240v]. you could draw 1800-2400 watts from a 120vac plug transform it to 240vac input that into an all in one and make up the difference from your battery bank to output 6000+ watts into the EV. this is what i plan on doing with my EV van conversion and of course i'll throw some solar into that mix

 

[parkswithpoints]

Could you use two chargers? one for a car and one for for a small trailer like a sqr drop? If you could hack the EV charger into the input of a 240v all in one unit you could maybe double up the charge and only turn the inverter on when you charge your EV remote.

 

[raz]

Most third party chargers have variable settings from 40a(9.6kw) to 16a(3.84kw) or even less amp

 

[meetyg]

I would think that the added weight of inverter and batteries would lower your range. I'm not sure you can build an effective system that will give you significant range that will compensate for the reduction in range due to all that weight.
I own an EV myself...

Just as an example if a small system, using what's called a granny charger (220v, 10A charges at about 2.2kw per hour):
My DIY 24v 100Ah 8s Lifepo4 battery weighs in at about 18kg. This gives you around 2.4kwh of battery power.
You would need an inverter. My all-in-one 24v 3k inverter weighs around 10-12kg.
That's already an additional 30kg, and we haven't talked about solar panels, wiring, breakers etc...

You need to factor in the effiency losses for inverting DC to AC.
So in short you will get something like 2kwh added to your EV battery, but your EV consumption will be higher even when not charging.

 

[raz]

It’s no practical yet until PV efficiency goes 50%. It’s 22% now

 

[rustythorn]

It’s no practical yet until PV efficiency goes 50%. It’s 22% now

multijunction panels are about 40% and near 50% with concentrators plus there is some new tech coming out soon that will boost multijunction panels a bit more, of course multijunction panels are incredibly expensive

 

[parkswithpoints]

Most third party chargers have variable settings from 40a(9.6kw) to 16a(3.84kw) or even less amp

Good point

 

[parkswithpoints]

multijunction panels are about 40% and near 50% with concentrators plus there is some new tech coming out soon that will boost multijunction panels a bit more, of course multijunction panels are incredibly expensive

Found this video, agree it doesn't look practical

 

[rustythorn]

Found this video, agree it doesn't look practical

that is not terribly effective design, however, with a custom design you can fit 2000 watts on top a van or 1300-1500 with off the self parts. plus we could skip having extra batteries and just charge the main pack directly but that would void the warranty

 

[time2roll]

Get the vehicle first. Then start exploring your needs. Or adjust travel plans around a charging source. I think the car will do better than expected.

 

[Ampster]

Get the vehicle first. Then start exploring your needs.

I whole heartedly agree. I had a lot of misconceptions before I had an EV with DC fast charging. Also, today there are many more charging stations than ten years ago.

 

[Ampster]

Found this video

1200 Watts per hour versus the increased consumption because of the drag of those panels in the back.

 

[rustythorn]

1200 Watts per hour versus the increased consumption because of the drag of those panels in the back.

i'm not saying that tesla setup is a good idea, however, 1200 watts of those panels is 43 lbs, about the same as a baby and its gear

 

[Substrate]

The bummer about those panels nearly flat on the hot black asphalt is that they could be overtemping and cooking the bypass diodes, that type of thing.

Maybe at least carry some elevation material, like little blocks, hinged swing-away feet etc, to at least get them up off the surface.

But yeah, practicality comes to mind. Like in the old days when some thought putting a long horizontal squirrel cage fan on top of the roof to recharge the batts while driving was a good idea. Wind drag, amongst the sound of having an industrial squirrel cage fan running just above your head as you drive.. But hey, at least this guy is thinking.

 

[chrisski]

I just got my Tesla Model 3. There is some loss in charging for things like parasitic draw and heating the battery. This makes charging harder than you would think at first. This is like a fixed cost. It doesn't matter if you are level 1 charging or level 2 charging, this loss is the same.

Level 1 charging can expect 3 to 4 miles an hour.

My Tesla was telling me I was getting between 200 and 250 watt hours per mile, but my calculations were showing me I was between 350 and 450 watt hours per mile. I knew something was off. The folks at Tesla must have worked as mathematicians or economists with for the government prior to getting hired on. Just like key things are left out of the consumer price index. Tesla seems to be showing on their app something a bit less coming out of my wall socket.

So knowing since Tesla is delivering over 1 million cars a year, I can't possibly be the first to have noticed this. That's where the internet revealed things like 600 watts to runthe battery heater every time you charged it and its the same amount as level 1 and level 2. The amount I turn the AC or heater on will effect the length of time needed to recharge.

This battery heater and climate controls don't seem to be included in Tesla's app that show I only spend 200-250 watt hours per mile when its actually 350-450. That's like telling me inflation is only 8% when the price of gas is over double in two years. It could be inflation is 8% if you don't have to eat, heat your house, or drive your car. Perhaps it is only 200 - 250 watts per mile if I pretend the other energy magically gets there somehow. Daddy's incredible disappearing dollar trick.

 

[curiouscarbon]

to be fair, at least the stuff is at the back of the vehicle where it ought to generate the least drag

 

[curiouscarbon]

I just got my Tesla Model 3. There is some loss in charging for things like parasitic draw and heating the battery. This makes charging harder than you would think at first. This is like a fixed cost. It doesn't matter if you are level 1 charging or level 2 charging, this loss is the same.

Level 1 charging can expect 3 to 4 miles an hour.

My Tesla was telling me I was getting between 200 and 250 watt hours per mile, but my calculations were showing me I was between 350 and 450 watt hours per mile. I knew something was off. The folks at Tesla must have worked as mathematicians or economists with for the government prior to getting hired on. Just like key things are left out of the consumer price index. Tesla seems to be showing on their app something a bit less coming out of my wall socket.

So knowing since Tesla is delivering over 1 million cars a year, I can't possibly be the first to have noticed this. That's where the internet revealed things like 600 watts to runthe battery heater every time you charged it and its the same amount as level 1 and level 2. The amount I turn the AC or heater on will effect the length of time needed to recharge.

This battery heater and climate controls don't seem to be included in Tesla's app that show I only spend 200-250 watt hours per mile when its actually 350-450. That's like telling me inflation is only 8% when the price of gas is over double in two years. It could be inflation is 8% if you don't have to eat, heat your house, or drive your car. Perhaps it is only 200 - 250 watts per mile if I pretend the other energy magically gets there somehow. Daddy's incredible disappearing dollar trick.

your experience is relatable. driving a model 3 for a few years and there is a significant amount of energy that goes into the BMS which involves fluid pumps and the air conditioner and resistive heating or heat pump etc.

many diy pack have no active heating, and very few have active cooling. but to get long life, extra energy input can seemingly help.

for DC fast charging, the BMS will generally try to pre heat the cells to 130 F to optimize charging.

the pre charging consumes energy and should be factored into charging efficiency in my opinion.

hope you have a good EV enjoy time! ? i really like the model 3