VW Transporter T5 Van EV conversion.
 

Here's a picture of said van:

http://ecomodder.com/forum/attachmen...1&d=1440205252

Now, I really love this van. Part of the reason I love it though is the 128kW/400Nm 5 cyl engine. It rockets to 60mph in around 9 seconds. It handles great, rides Ok and is very comfortable.

Kerb weight is listed as ~3800lbs, my payload might push that up to 5000lbs max (I figure there must be 400+lbs in the ICE, fuel and ancillaries). I'd like a 60mph top speed and I need 60 miles of range, however I only really need to do 40mph max most days and usually only drive 30 miles per day, with a lifetime average speed of 20mph.

I do want to keep the current level of acceleration that makes this van so fun at traffic lights (if not better it:D). I know there are motors out there that can do this. The van is currently rated to tow 4400lbs, and I'm guessing that as long as I use the gears, that shouldn't be a problem (range reduction aside).

My main question is how much battery do I need (in terms of Wh, cost and physical size? I've done some research, but most of what I've found is a few years old and obviously battery costs keep falling. Do I use average speed in range calculations? My GPS also stores my moving average which is probably more appropriate (I don't remember this off hand).

I figure if I no longer care about the current ICE and just run it until it dies, it lets me save up in the mean time, batteries will only become more affordable, and I've got time to get the A/C, power steer etc EV ready while I wait.

Wow, $18k to fix the cylinder head!? That's ridiculous. Love the plan, though... subscribed.

I'd probably rather drop an Isuzu 4JH1 as a replacement to the 5-cyl TDI and call it a day. Anyway, if you're really into converting the van into an EV, I'd suggest you to consider turning it into 4WD with a direct-driven motor at the rear axle.

The Isuzu makes less power and torque from a bigger engine, and in the Rodeo is thirstier. A backwards step in my book, reliability counts for something though.

Admittedly my mechanical skills aren't great, and I feel more likely to complete an EV conversion than I would an engine swap (plus there's actually an EV converter near me if I really get stuck). Ideally, I'd fix the head myself, but I wonder if that's a smart move if Euro and VW specialist mechanics don't want to touch it.

Back to the EV conversion.

I used 8l/100km on my last tank (about average). I figure about 1l/100km is wasted idling (I don't like to shut down my turbo cars repeatedly), so we should have a safety margin.

The EM calculator tells me that equates to 710Wh/km.

I want to travel 100km on a charge so I need a 71kWh pack. This is at odds with the EV source calculator which predicts a nearly 60 mile range on a 28.8kWh pack. They don't factor in that I drive all low speed streets and would be hypermiling, I expect I would see a healthy 80miles on such a pack.

This pack will cost $12K and weigh 700lbs. My van has a good amount of space under the floor so all the batteries would be mounted below my CG, improving ride and handling (maybe!).

How would I more accurately predict my required capacity based on my current diesel usage?

Jack Rickard is getting 750 - 1100 w-h per mile in a 7777 lb cadillac escallade running DC motors and an automatic transmission. In my opinion, your van should do quite a bit better than 710.

Based on 3800 lbs a decent conversion should get you 380 w-h per mile. A bad conversion maybe 450 w-h per mile. A Great conversion 350 w-h per mile. Do you run cargo or towing a lot? If not, I would not put the extra weight into your nominal calculations.

With low-speed driving and hyper-miling, running an AC system and using regen to stop at lights (when coasting in traffic just won't cut it) I'll bet you could beat 350 w-h per mile.

100 miles with a margin for error, and using some heat, and maybe power steering and brakes ... 400 w-h per mile ... 10% margin for error or if you want to charge to 95% and discharge to 10% (in an emergency case) .. 45 kw-h would be my guess.

If you have the room, centering the mass of the batteries at the centerline of the wheels is supposed to affect the handling of the vehicle the least. This is what I read of Teslas and such. I have no experience with having lots of room for batteries ;)

That's an excellent question that I've never read before. There are a few things you use fuel for when stopped that electrics don't, like idling .. but there are things you get for free, like heat, that electric uses energy for. I would think there are too many variables to get a decent converted number.

Thanks for the input. I think 4400lbs is about right for a typical loaded van with the expected added weight of the conversion factored in. I have a 1000lbs trailer that I tow quite often, but I plan on building a lighter 6-700lbs version soon. I could fit a generator to the trailer for occasional last resort use. The EV calculator predicted range doesn't change as much as I expected when I play with the curb weight. From 3800 to 5000lbs reduces range by 14 miles, which typically won't be the end of the world.

What's the most popular way to run the A/C? I think running it off the drive motor is out as I spend too much time stationary. I definitely like the idea of cooling off the interior before I get in it. Has the Prius A/C compressor been cracked?

It's front wheel drive, so I'll have to put a lot of batteries under the hood or it will just be forever spinning it's wheels (the rest will go under the floor as far forward as possible). It already has wheelspin issues :) I think an electric motor will be easier to modulate than a TDi in this regard. When I fitted a tuning box to add 50Nm it made it peaky and quite unpleasant in first and second.


I pretty much know I use 1l/100km idling. That figure is from an older van with an MPGuino that actually logged fuel used while stationary. I do pulse and glide (engine on in neutral) with the newer van so there's more fuel wasted idling while moving so as not to kill the turbo. I suppose if I really did EOC and idle stop at lights I might get my consumption as low as 6.5l/100km.

I'm surprised there isn't an established formula for converting fuel use to electron use. It would surely be more effective than using vehicle weight as the only input, ignoring aero drag and required speed.

If a heater wasn't a legal requirement, I would probably not bother fitting one.

Is it more common to run DC:DC converters or to retain separate 12V batteries? I'm thinking my 12V battery would be grid charged and sized to match my EV range, my 12V usage wouldn't affect my range that way. The roof has space for ~500W of solar panels which would probably be enough for my 12V requirements.

Using a generator to extend range is a good idea. There are implementation issues. Normally you have an interlock to disable the controller and ensure that the car does not move when you are still plugged into the charger. Many chargers have been ripped off garage walls, and cord ends have been wrecked if this is not implemented. Charging while rolling presents an issue to this interlock. Starting and stopping the generator while driving is another issue that can be avoided by doing the once-in-a-while start while stationary on the side of the road.

Sorry about that. I was talking about running an Alternating Current or AC motor, instead of a DC motor, for driving the van.

There are Air conditioning compressors available. I don't run Air myself, so I don't have experience.

Depending on the motor you choose, you may not have to put as many batteries in the front as you may think. A UQM Powerphase 100 brushless DC motor is about 110 lbs and the controller is another 60 lbs. That's on the low side of the weights and the controller is liquid-cooled. A Siemens 1PV5135-4WS14 AC Induction Motor is about 200 lbs (without cables) plus the adapter plate - another 30 lbs or so (I can't locate that info at the moment) and the DMOC645 (a compactible controller) is about 60 lbs. That's the heaviest single-motor solution I've seen The motors and controller are both liquid cooled so you need to keep the radiator/fan/pump.


I think that's how the EV calculators work. There is a HP requirement based on rolling resistance (friction) of tires on the road that has to do with weight plus the wheel bearings and transmission losses, that is not dependant on aerodynamics, then there is an acceleration portion that has a lot ot do with weight, and finally there is the aerodynamics portion. The last one, as you know, rises exponentially with speed.

I expect to need mine mostly to keep the windows clear when it's raining. It's not rolling as yet, so I guess we'll see.

The DC/DC converter is one of the things in an electric car that appears to have problems. I think it's the part that I've heard replaced the most. Most times you need a small 12V battery anyway, to close the contactors on the large pack. So if it's there anyway, making it a bit bigger is not an issue. If you are intending to use the generator on the trailer, you will run out of 12V battery while you are charging your main pack if you have no way of charging the 12V. Lots of stuff uses 12V and you may have some challenges sizing a stand-alone 12V battery. That said, all of my testing is done with a stand-alone 12V system. I use a DC/DC in my car with a 10A 12V lithium 'starting battery' and the DC/DC supplies 30 amps (which is very low). I guess I'll adjust the size/output of the DC/DC if it causes me trouble.