Hybrid Car Technology vs. Solar Energy Technology

[kllcbosmetris]

Explain this to me? How is hybrid battery technology different than solar battery technology? I hear that you can use the existing hybrid car battery (i.e. Prius) to run the A/C or heat (by using car's OEM fan) without running the car. How is that electric car battery different than a lithium battery you install with your solar set up? How can a solar lithium set up be integrated with the existing car systems like a fan outlet, etc.? Is it possible to borrow some technology (or just buy the electric car battery, if they are so superior) to make it more compatible with the existing car set up? Really curious about this.

 

[MrAlvinDude]

A hybrid car has electric motors to run everything that is needed while driving. And the combustion engine is basically hooked up to a big electric generator. And the generator can power all the electric motors needed to run the car, and/or charge up the batteries. 
If a hybrid car had enough surface, then the combustion engine and generator could theoretically be replaced by solar panels. 

The reason that electric cars (and hybrid cars) are now available is mainly because of the lithium battery technology. The lithium battery technology is lighter, can be charged faster, can be drained deeper, and be discharged and re-charged more times than other known battery technologies. 


I doubt that hybrid car batteries are any cheaper than any other lithium batteries, they are mainly shaped so they fit into the design of the car. So weight distribution of the car is still good, and there is stil space in the trunk and cabin etc. 
So I do not think there is any advantage to try to use the shapes of a hybrid car battery, compared to other squared-box lithium batteries. 


The reason why A/C or heat in a hybrid car can work directly off the battery, is because they are designed that way. They are basically powered by their own dedicated electric motor.   
Ordinary cars will typically be mechanically connected directly to the combustion engine, and thus the engine needs to be running to power the A/C or heater.
Some newer cars (that turn off the engine while they are waiting at a red light) they might have an electric motor to power the A/C, and they will be able to run the A/C from the battery for the minute or two that you are waiting at the red light. 

I believe that there are after-marked battery packs, that could be integrated into hybrid cars, to extend the battery, or replace it when the original wears down. 

And I seem to have seen youtube videos that show where there are plugs, so solar could be connected to the batteries on hybrid cars. 
But generally speaking the surface of hybrid cars are so small that it does not make much difference to add a few hundred watts of solar.
Adding solar to a trailer of some kind, and using that to add to the charging of the car battery might improve your mpg, as the gasoline powered generator might need to run a little less.

 

[tripper]

I have an older Hybrid car, it runs on NiMH (nickel–metal hydride) batteries, not as good as lithium but no where near as finicky. The pack in my car is 144 volt NiMH (nickel metal-hydride) battery,
consisting of 120 cells providing 1.2 V each rated capacity 6.5 Ah . I do know they can take some insane discharge and recharge rate (C rate). The pack is about as big a 1 1/2 milkcrates, cost $2500 from China (originals were $4000).

I'm sure it is cheaper and safer to build a good LiFePo4 pack than use a hybrid battery pack for an RV.

 

[John61CT]

There are separate types of questions here.

One is a general "how does it work? " maybe drilling down to specific subsystems.

IMO that requires specifying what make / model range you're asking about, since they do vary, e.g. Toyota has patents that make their system unique.

Also, general intro information is easily found by googling.

The other type is "if I had an X (e.g. a 2010 Prius) how could I do Y (e.g. use it as a generator and battery bank for my off-grid cabin) ?"

Note you would probably get more / better answers to such Q's from the DIY EV forums full of hobbyists trying to reverse-engineer these power systems, make use of salvaged batt packs to be used with generic chargers etc.

That's where the tech knowledge lies, but they have little to no interest in House bank storage for off-grid living, they are EV guys.

There is a Prius camping guy on YouTube that has HowTo info on adding a second batt to the Prius built-in, but not techie, basic stuff.

Do please post specific stuff here as you find it, several people here have generally expressed interest in the topic.

 

[scottorious]

This is a good post. I stumbled on a chevy volt salvage battery that I might buy and for the price I can get it for it would be cheaper than comparable storage in lead acid batteries. 16 KWH of power for 1200 bucks. They can be broken down easily into 48 and 24 volt packs. That's not a super useable voltage for RV folks but with a DC to DC converter it gets close! Just kind of a pain to charge and keep safe.

 

[Redbearded]

I think the main issue with using something that is lithium out of a vehicle is that it's the flammable kind. The Lithium that people talk about using on here is usually LiFePO4 which is a much safer chemistry. It's a tradeoff for sure, but I'll take a bit of peace of mind with 8-12 cells which won't explosively fail if mishandled (with little to no warning), especially if it's in a place I sleep... If I had a shed out back which I just used for something like the volt or Tesla battery it would be fun to experiment, but I would have to be prepared to lose everything nearby. Also the Volt power pack uses ~288 cells and chances are, if you get one, it is out of a wrecked vehicle. The question is, do you trust that you can maintain all 288 cells (charge, discharge, monitor for heat, etc) also please note that the Volt's cells typically are fluid cooled in the pack for a longer life. I'm not saying it's impossible, it isn't, but there is little room for mistakes, and high penalties for slight errors.

 

[John61CT]

One day there will be open-source hardware allow you to drop in a Tesla or Volt pack and safely use it as a House bank.

I eagerly await that day, but until then will let other pioneers collect the arrows in their backs.

And stick to paralleled 4-packs of bare prismatic LFP cells.

Which many who favor packaged proprietary BMS systems, in turn call "DIY" and consider foolishly dangerous.

 

[kllcbosmetris]

I think the main issue with using something that is lithium out of a vehicle is that it's the flammable kind. The Lithium that people talk about using on here is usually LiFePO4 which is a much safer chemistry. It's a tradeoff for sure, but I'll take a bit of peace of mind with 8-12 cells which won't explosively fail if mishandled (with little to no warning), especially if it's in a place I sleep... If I had a shed out back which I just used for something like the volt or Tesla battery it would be fun to experiment, but I would have to be prepared to lose everything nearby. Also the Volt power pack uses ~288 cells and chances are, if you get one, it is out of a wrecked vehicle. The question is, do you trust that you can maintain all 288 cells (charge, discharge, monitor for heat, etc) also please note that the Volt's cells typically are fluid cooled in the pack for a longer life. I'm not saying it's impossible, it isn't, but there is little room for mistakes, and high penalties for slight errors.

Are you saying electric cars are more dangerous to drive because the battery used in the vehicle is more flammable and dangerous as a result (i.e., in case of an accident)? Is that a common knowledge amongst electric car buyers?

 

[kllcbosmetris]

The reason why A/C or heat in a hybrid car can work directly off the battery, is because they are designed that way. They are basically powered by their own dedicated electric motor.   
Ordinary cars will typically be mechanically connected directly to the combustion engine, and thus the engine needs to be running to power the A/C or heater.
Some newer cars (that turn off the engine while they are waiting at a red light) they might have an electric motor to power the A/C, and they will be able to run the A/C from the battery for the minute or two that you are waiting at the red light. 

I'm trying to understand whether an 'electric motor' set up you mentioned can be implemented on a DIY camper van, in a way that you gain the ability to use your van A/C (re: some vans have rear A/C vents) set up -- which removes the need to have a roof-cut Maxx or Fantastic Fan. Would you mind elaborating on that possibility? Any type of alteration that can be done under the hood to create that 'use the built-in factory vents' option?

 

[John61CT]

No, but it's the fancy and proprietary protective electronics that keep them safe.

The hobbyists are very busy trying to reverse engineer those bits, sniffing for CAN messages etc.

The bare cell chemistries are indeed very risky, try shipping them by air these days.

 

[kllcbosmetris]

you would probably get more / better answers to such Q's from the DIY EV forums full of hobbyists trying to reverse-engineer these power systems,  make use of salvaged batt packs to be used with generic chargers etc.

Do please post specific stuff here as you find it, several people here have generally expressed interest in the topic.

Could you recommend a DIY EV forum? 

I'm trying to understand why van conversions do not have systems similar to electric cars where we can just ran an A/C or heat via vehicle's existing vents (without running the combustion engine or depleting the starter battery) similar to what Prius campers are doing. The way I see it this can be done by "DIY Prius-like system" or "use an old Prius system." [Replace 'Prius' with any electric car set up]. My ideal stealth system would have a similar set up to electric cars where you can also charge your DIY van on a privately owned (re: that you have a right to charge) or pay (by credit card) electric charge station.

 

[John61CT]

Same thread over there

http://www.diyelectriccar.com/forums/showthread.php?t=190722

 

[John61CT]

I'm trying to understand why van conversions do not have systems similar to electric cars where we can just ran an A/C or heat via vehicle's existing vents (without running the combustion engine or depleting the starter battery) similar to what Prius campers are doing.

The economic reason is that 99% of RVers in the US just plug their rigs into the campground shore plug when they travel.

If off-grid dwellers were a market worth pursuing commercially the we would see more energy efficient setups.

But that in itself does not speak to whether or not the way you're talking about would be the way to go.

The way I see it this can be done by "DIY Prius-like system" or "use an old Prius system." [Replace 'Prius' with any electric car set up]. My ideal stealth system would have a similar set up to electric cars where you can also charge your DIY van on a privately owned (re: that you have a right to charge) or pay (by credit card) electric charge station.

Take stealth out of the picture, just complicates things further.

And as I mentioned before the Toyota hybrid setup is unique, they have all kinds of long-term patents.

And plug-in EVs as opposed to fossil-fueled hybrids are a completely different kettle of fish.

I would suggest you start by visiting showrooms and pretending you're in the market, get the sales teams to teach you how they work.

Google a lot, download books and brochures, find regular user forums for each model and ask basic Q's.

That EV forum will be useful if you want to identify an engineer to design a prototype of what you're dreaming of.

 

[John61CT]

Good example of the level of discourse there

http://www.diyelectriccar.com/forums/showthread.php?t=190266

 

[MrAlvinDude]

I'm trying to understand whether an 'electric motor' set up you mentioned can be implemented on a DIY camper van, in a way that you gain the ability to use your van A/C (re: some vans have rear A/C vents) set up -- which removes the need to have a roof-cut Maxx or Fantastic Fan. Would you mind elaborating on that possibility? Any type of alteration that can be done under the hood to create that 'use the built-in factory vents' option?

Okay, so you mainly want to be able to move air, not necessarily cool or heat it.  As roof mounted fans only move air. 

The ability to move air through the vents, is already done by electric motors in all the cars I have been in touch with. So to power the fan from a house battery, a switching relay is needed, that switches between getting power from the engine system or the house system, and you will be able to run that fan. 

If there are air ducts way in the back of a van, then there might be a secondary fan where you need to add a similar switching relay to. 
And if there are individual temperature zones in the car/van, then there are very likely a fan for moving air in each temperature zone. 


But the principle to get air moving in the already installed vents, is the same: "Just" add a relay to switch powering those fans from the house battery. 


It is however very likely that those air-duct fans, use much more power than the roof mounted fans. 
In my last car the air-duct fan motor had its own 30 amp fuse. 

I don't know the max amp draw of those roof mounted fans, but I expect them to be in the range of 4-6 amp at full blast. 

Now, the car air-duct fans may not need to run full blast, so their effective power draw may be less (in the 6 to 12 amp range) , but they will typically draw quite a bit more power that the roof fans. 
One reason being, that they have to push the air through all those turns and shapes of the air-ducts. 



So though it may turnout to not be very practical (due to being too power hungry), that is the way I would run those car fans from a house battery.

 

[kllcbosmetris]

Okay, so you mainly want to be able to move air, not necessarily cool or heat it.  As roof mounted fans only move air. 

Moving air, at the very least, would be great for sure. Up until now, I didn't know I could use the van's existing built-in A/C vent to move air -- without running the car that is. Ideally though, I'd like to have a set up where that air is cold or hot (as Prius campers do -- if I understand it correctly, they can run their car's AC or heater even when the car is not running?) just as if I start the engine and run the A/C or heat. Now, if those options are super complicated, I can settle with just the 'move air' ventilation, as I was thinking about getting Webasto 2000 AirTop heater to deal with heating -- but if I can use the existing car set up somehow, that'd be even better. Basically, I'm trying to keep the van as stock as possible, without cutting the roof (which is not an option for me as I want to keep stealth and also want to use the roof space for max. solar) or cutting the floor to create air ventilation. 

The ability to move air through the vents, is already done by electric motors in all the cars I have been in touch with. So to power the fan from a house battery, a switching relay is needed, that switches between getting power from the engine system or the house system, and you will be able to run that fan. 

I'd love to know more about this. Can you guide me in the right direction? Is there a place/forum that explains that process (with what you need to buy to make that happen). If not, where can I get that done (if I have to pay someone to do it)?

If there are air ducts way in the back of a van, then there might be a secondary fan where you need to add a similar switching relay to.  And if there are individual temperature zones in the car/van, then there are very likely a fan for moving air in each temperature zone.  But the principle to get air moving in the already installed vents, is the same: "Just" add a relay to switch powering those fans from the house battery. 

Yes, there is a secondary fan vent (see attached picture). 

Basically the reason I thought about electric car set up is because I'd like to be able to use van's manufactured system as much as possible. I figured if electric cars can do what I need (ventilate, run AC or heat without starting the car/van), either DIY their battery system to power heat or A/C (like they do) or just purchase their set up from a used or salvaged car. Lastly, I thought being able to charge the car at electric charging stations would be tremendous for me, as I have a few stations around me that I can legally use. So I'd do 'shore power' to reload my house batteries at those stations (instead of RV camping sites).

 

[John61CT]

Since the fans included in vehicles' systems are designed to run when the engine is on, they are rarely energy efficient.

And I bet in newer vehicles controlled by the onboard computer rather than directly.

Plus messing with the car's wiring may well create warranty issues.

Feel free to experiment away, just sayin. . .

 

[Bdog1]

The secret sause is the 400v electric AC compressor. You add that to your van system and run the interior fan and a condenser fan and you"vs got cold AC


Sent from my iPhone using Tapatalk

 

[Bdog1]

Stop start vehicles just restart if interior gets too hot or cold.


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[John61CT]

The many different kinds of EV charging stations require intelligent handshaking signaling from the car's computer as to voltage, SoC, amps capacities etc.

This signaling will need reverse engineering as well, and if there does come a day that people have figured out how to use these scarce and highly subsidized stations for purposes other than intended, I'm pretty sure TPTB will figure out how to put a stop to it.

Unless you mean buying one to put in your garage, as of course many plug-in EV owners do, at say $1,500 plus electrician labor rates.

Note this topic has nothing to do with regular hybrids like the original Prius, only with the plug-in EVs.

The Prius runs off gas just like regular cars.