Charging my new EV from a bank of panels

adasadas Solar Expert Posts: 136 ✭✭✭✭✭
Aloha, All. I bought an electric Yaris off Ebay and hoping to charge it from my electric grid. I can designate 12x195W panels and an Outback MX80 to run at 60V and the car is 240V. Seems I could charge 4 banks @ 60V each for 1-2 hours each, but How to do it?
I would want a fool-proof way and not have to manually switch each bank to be sure I do not do a +to- short.

Maybe here are a couple solutions that may work??
Some kind of master switch that can disconnect four terminals to isolate the 4 banks (that are normally in series) and simultaniously connect the four banks to the charger?

Ideas? thanks
francis

BTW here is the Yaris I bought
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=270660837843&viewitem=&sspagename=STRK%3AMEWAX%3AIT

Comments

  • nielniel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Charging my new EV from a bank of panels

    are you off grid or grid tied as i don't recall? if you are grid tied it would be better to send your solar power to the grid so that you can charge the ev at any convenient time otherwise the car shall need to stay parked to charge while the sun shines. if off grid you can charge up an extra large battery bank just for the ev and then use that power to in turn be inverted if necessary to be able to charge the ev. forgive me as i don't know what your ev requires to charge, but you get the idea i think.
  • adasadas Solar Expert Posts: 136 ✭✭✭✭✭
    Re: Charging my new EV from a bank of panels

    Aloha, Neil. I am off the grid. To charge the car up to 240VDC at a reasonable 20-30 amps I would need a 220V inverter then a proper 220v charger. Just thinking to why not use the power off the Outback set at 60v output. (5x12v Optima batteries times 4 banks) total of 20 optima 12v batteries.

    Alternatively I could have a 12v x 15a charger for each battery and not depend on the max sun. (But I am in Hawaii and there are very few days a year that we do not get max sun). In the last 2 years since I installed the system, I have Never had to start a generator and the 8 old forklift batteries, I just add 5 gallons of water or so a week from my reverse osmosis water.

    thanks
    Francis
  • BB.BB. Super Moderators, Administrators Posts: 32,746 admin
    Re: Charging my new EV from a bank of panels

    Adas (Francis),

    Welcome back--has been awhile. I guess you have your off-grid fab shop/business working well in paradise?

    Hmmm Wonder if that new (yet to hit the streets) Xantrex / Schneider 600 VDC input solar charge controller can charge a 240 VDC car??? Would be an interesting public relations opportunity if they could do a "one off" high voltage battery charger.

    But, I keep coming back to wondering about the desirability to charge a vehicle directly from the sun. Efficiency can be much better--however unless you are a vampire and only drive the vehicle at night (;)) it seems to be fairly limiting to force the car to be locked to a charging station when the sun is up.

    Having a separate battery bank that can charge during the day, and recharge the vehicle at night (or even "quick charge" during the day) seems to be a reasonable solution (at the cost of an extra battery bank and less efficiency--both huge drawbacks).

    I keep thinking about the hardware--and unless you go standard (6kW 48 volt inverter and PV system) with standard 240 VAC charger for the car--Your otherwise left with a full custom design with high voltage and high power DC battery banks... Not something to take lightly.

    So learn from this one:
    A three-alarm fire that damaged a San Carlos warehouse containing memorabilia belonging to rocker Neil Young started in a vintage car that he had converted into a hybrid vehicle, authorities said today.

    An investigation determined that the fire started in a 1959 Lincoln Continental and spread to the warehouse. Young had outfitted the car with electric batteries and a biodiesel-powered generator as part of his company called LincVolt.
    ...
    "We are still investigating the exact cause, although it appears to be an operator error that occurred in an untested part of the charging system," Young said. "We do know that the car has been operating perfectly for almost 2,000 miles and the system in question would not be in use while driving the car. We are investigating the components involved with plug-in charging."

    www.lincvolt.com

    I can think of an Outback/MPPT charging 1/4 of the car array at a time (or four Outbacks) but each electrically isolated... However, that is probably not possible to do safely... From the above LincVolt link:
    However, the LincVolt suffered a disastrous accidental fire stemming from human error. The car was plugged in to charge and left unattended. the wall charging system was not completely tested and had never been left unattended. A mistake was made. It was not the fault of the car.

    I think, whatever solution you choose--will have to be pretty much goof-proof for everyone's safety.

    If you end up making a charging station--that certainly can be used to supplement the other portions of your shop when you have excess power available.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • mike95490mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Charging my new EV from a bank of panels

    Go with installing a Grid tie system. It will feed 100% of your PV harvest to the grid.

    If you are only using the PV for recharging, A LOT of PV capacity will be lost to a 3,000 watt array feeding only 1,100w to partially charged batteries.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • mike95490mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Charging my new EV from a bank of panels
    mike90045 wrote: »
    Go with installing a Grid tie system. It will feed 100% of your PV harvest to the grid.

    If you are only using the PV for recharging, A LOT of PV capacity will be lost to a 3,000 watt array feeding only 1,100w to partially charged batteries.

    I would be very surprised if your electrical service only was 110V at the meter. Do you have 3 wires from the power pole, or 2 ??
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • BB.BB. Super Moderators, Administrators Posts: 32,746 admin
    Re: Charging my new EV from a bank of panels

    I believe he is completely off grid (don't remember if by choice or by location)...

    -Bil
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • adasadas Solar Expert Posts: 136 ✭✭✭✭✭
    Re: Charging my new EV from a bank of panels
    niel wrote: »
    are you off grid or grid tied as i don't recall? if you are grid tied it would be better to send your solar power to the grid so that you can charge the ev at any convenient time otherwise the car shall need to stay parked to charge while the sun shines. if off grid you can charge up an extra large battery bank just for the ev and then use that power to in turn be inverted if necessary to be able to charge the ev. forgive me as i don't know what your ev requires to charge, but you get the idea i think.

    Aloha, Yes i am off the grid. I made one Outback 60 for the charger and divided the 14 12v series batteries Optima batteries in the car to 3 banks of 5,5,4 and set the charge controller to 73.00v absorb @ 10 minutes and 67.5v float to finish. It worked perfectly. 10 minutes seems to good for total absorb, but may try 20 min. Problem is that if there are a lot of wispy clouds coming through the controller will hang out at 71 to 72v and not start timing the absorb 73v much. and may over charge because the batteries are only 50ah and probably only wanting 25ah at 40% SOC. Anyways it works great, except having to switch 3 times. Any high voltage charge controllers out there or any step-up charge controllers? thanks Francis
  • nielniel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Charging my new EV from a bank of panels

    i do hope you charge the 3rd string separately as it has different requirements than the ones with 5 batteries in it. there isn't any easy answers for such a need as you have and the latest controller (the classic) isn't able to accommodate a 240vdc battery bank as you can see by the chart below. (borrowed from midnight solar discussion forum)

    the only other alternative is to store power into batteries as per normal solar setups with high power storage capacity and then invert it up to a proper ac voltage to be used with a charger designed for that said voltage and current requirement. if this is a commercially made ev then they usually provide chargers suitable for either 120vac or 240vac. if a homebrewed ev then you have a bit of a design nightmare in getting it all to work well and conveniently for you as you will need a special charging circuit.
  • halfcrazyhalfcrazy Solar Expert Posts: 720 ✭✭✭
    Re: Charging my new EV from a bank of panels

    You can use 2 of the Classic 250ks units together to charge a 240vdc bank. I would recommend going over to our forum at MidNite solar and we can open a line of discussion but this has come up a few times now.
  • nielniel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Charging my new EV from a bank of panels

    you've got my attention on how that is possible to do with 2 classic 250s seeing it say a maximum of 96v output. the 2 classics in series would equal 192v assuming the outputs can be seriesed.
  • halfcrazyhalfcrazy Solar Expert Posts: 720 ✭✭✭
    Re: Charging my new EV from a bank of panels

    The 250ks or Kangaroo Special is designed to charge a 120vdc battery so 2 would do a 240vdc battery. I will point Robin to this thread if needed but the OP would be better off to start a thread on our forum at MidNite.
  • nielniel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Charging my new EV from a bank of panels

    actually, it would be good on both forums.
    the link for midnight solar is,
    http://www.midnightsolar.com/
    and just click on forum on the upper right.
  • AntronXAntronX Solar Expert Posts: 462 ✭✭
    Re: Charging my new EV from a bank of panels

    I would research possibility of modifying existing cheap square wave inverter to output regulated high voltage DC into car's battery bank directly. For a fee, you may find an unemployed electronics engineer to do the job for you. I think the best strategy is to avoid splitting your solar array. If you can get 24V to 240V DC converter going, there is an option to engage car charging using only excess current from your solar array that your main 24V battery bank cannot absorb. This way your main 24V system bank is charged first, then excess solar current will automatically flow into your car.
  • Peter_VPeter_V Solar Expert Posts: 226 ✭✭✭
    Re: Charging my new EV from a bank of panels
    adas wrote: »
    Aloha, Yes i am off the grid. I made one Outback 60 for the charger and divided the 14 12v series batteries Optima batteries in the car to 3 banks of 5,5,4 and set the charge controller to 73.00v absorb @ 10 minutes and 67.5v float to finish. It worked perfectly. 10 minutes seems to good for total absorb, but may try 20 min. Problem is that if there are a lot of wispy clouds coming through the controller will hang out at 71 to 72v and not start timing the absorb 73v much. and may over charge because the batteries are only 50ah and probably only wanting 25ah at 40% SOC. Anyways it works great, except having to switch 3 times. Any high voltage charge controllers out there or any step-up charge controllers? thanks Francis

    You might want to look into something like a "Lee Hart Battery Balancer"

    As described on http://www3.telus.net/nook/balancerland/balancer/index.htm
    "The Battery Balancer is a system that tries to keep the set of batteries in an electric vehicle "balanced" by shuttling charge to the weaker/lower capacity batteries in the pack so that the batteries will all reach empty at about the same time when they are discharged and full at about the same time when they are recharged."

    Basically what it does is periodically scan your batteries and connects a charger to the one with the lowest voltage.

    Typically this charger is an isolated DC-DC converter that has it's input connected to the entire pack (168V in your case) and it's output is connected through one of numerous relays to the weakest battery.
    However there is no reason you couldn't use a bunch of solar panels instead. You could probably set it up to charge in 24V banks, maybe even run a couple banks at the same time.

    The whole thing is open source so you can modify the hardware and software anyway you want.
  • mike95490mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Charging my new EV from a bank of panels
    Peter_V wrote: »
    You might want to look into something like a "Lee Hart Battery Balancer"

    As described on http://www3.telus.net/nook/balancerland/balancer/index.htm
    "The Battery Balancer is a system that tries to keep the set of batteries in an electric vehicle "balanced" by shuttling charge to the weaker/lower capacity batteries in the pack so that the batteries will all reach empty at about the same time when they are discharged and full at about the same time when they are recharged.".....

    cool info, I'll look further and see if it can be used for LiPo4 battery bank.

    Anyone done any comparisons recently between Lead Acid, LiPo4, NiFe battery technologies ?
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • Peter_VPeter_V Solar Expert Posts: 226 ✭✭✭
    Re: Charging my new EV from a bank of panels
    mike90045 wrote: »
    cool info, I'll look further and see if it can be used for LiPo4 battery bank.

    Not really. LiPo needs a much more intricate battery management system. They require individual cell management to make sure that no cell gets over charged or discharged.

    They make circuits specifically for this that have the ability to bypass individual cells when they reach their limits.
Sign In or Register to comment.