# Is my Benz too fat? (planning a '99 C230 Build)



## ChaseDE (Feb 16, 2012)

Hey all!! new here to the site, nice site you have here. I am planning a EV Conversion on a 1999 Mercedes Benz C230 Kompressor. Well, right now I am gathering info.

About Me:
I am almost 30, and I live in Delaware. I am married and have 2 kids. I work as a mechanical piping and equipment designer for a very large international engineering firm. I mainly use Aveva PDMS 3D design, I also have extensive knowledge in AutoCAD. PS: I am a forum-a-holic...and I hate facebook.

All the men before me in my family have been mechanics or worked in the auto industry, my grandfather was a 18 wheeler mechanic for many years and I inherited his vast collection of snap-on tools. My dad retired from Chrysler 15 years ago.

I currently drive a 00 Chrysler Concorde, my wife a 06 Honda Pilot. I do all the work on the cars myself, they never go to the dealer. I am rather handy with working on cars, my dad taught me a lot.

About The Build:
My mom has had a 99 Mercedes C230 Kompressor (4cyl. supercharged) for quite a while, it has gradually started having little issues here and there. It is to the point my dad gave up and offered me the car, for free, if i could fix it. it has a cracked heater core and a bad cam rattle. to do the heater core i would have to pull the dash, blah, blah, and i was planning on doing this. the car is now in my name, in my garage, sitting....waiting.

I own a decent little online forum for Delawareans called talkdelaware.com and one of my members recently posted a story from the beach about a guy that converted his S-10 to all electric, a light bulb went off in my head *ding* lets convert the benz!!

You see, i only drive my car to work really, 25 miles ish round trip. And i'm kinda bored too, and I have this car, and well, it seems like a decent idea. on top of this i know the guy who owns a large interstate battery store near where i live and may be able to smooze him into sponsoring the project, maybe all the batteries....we will see on that. my uncle in law has a lot of fab skills, he rebuilds and restores old muscle cars.

I ran this by my dad and he thought it sounded pretty cool to him, he said if it is feasible he would help me out.

Specs and Such:
99 C230 Kompressor, 4 door, auto with sport shift, 3200 lbs curb weight. the car is really in great shape, no rust.

shes a bit on the heavy side at 3200 pounds with the ICE, i saw a guy talking about his miata that he wants to get down to 2000, idk if i can get this there.

very strong/stiff suspension: idk if i would have to beef it up more to hold batteries or what, anyone have a guess?

it is auto with sport shift, so you can actually select gears 1-4 and then put it in D for overdrive. see image here, mine is the same except mines carbon fiber. i realize this is not ideal for EV but i did read some threads that gave me hope.

power everything, i realize this is also not ideal. i would like to keep the power stuff though if possible.

range, 50 miles or so, like i said, it would only go to work and back really 30 miles roundtrip.

performance, it is a little beast of a driver right now, it has great acceleration. that said, im not looking to smoke the tires, just a decent get-up. my concorde has the baby v6 in it, and it's big, and slow, im fine with that.

financing, well, i am pretty sure i can get my buddy to sponsor it for the batteries. so lets so $5k NOT including batteries. so $5k for other stuff, controller, motor, etc, etc.

this will be a slow build, over time, nothing that needs to get done asap. right now im in the gathering info stage and would love to hear you vets thoughts on my idea.


-Chase


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## Bowser330 (Jun 15, 2008)

The car is great, RWD is the way to go to utilize more of that low-end torque.

The batteries are okay for a first time conversion but they are heavy...

125AH cell 12V each, 12 in series = 144V * 125A = 18,000W = 18KW
For longevity of Lead acid batteries you should only discharge 50% so = 9KW
Your heavy EVbenz will consume at least 300wh/mile = 30 miles range
125AH cells can be heavy...
http://www.interstatebatteries.com/...868-2147384810-4285691076&Title=12V+119AH+SLA
This one is 110lbs each...
12 batteries = 1,320 lbs for the pack....!!!

5K$ might just be enough for the motor + controller, but dont forget the other pieces, like DC-DC converter, Charger, elec power steering...etc


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## ChaseDE (Feb 16, 2012)

Thanks for the welcome and the confidence boost Bowser, I was prety worried about the car. 

I am not locked into interstate really, I haven't talk to him yet or anything but he does love this stuff.

If there is a battery that may be better (and cheaper) for a build like this i would definetly consider it.

i was looking at a ev conversion chart and it looks like the trojan t-105? batteries are pretty decent too in a 144v configuration.

again, i am a TOTAL noob to this stuff, the most i do electrically is build and sell electronic cigarettes, lol, they max out at 6 volts.

btw, i do a lot of website design and building, graphics, etc. always willing to barter services...hint hint vendors......hahahaha

j/k....kinda


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## mora (Nov 11, 2009)

I believe your car is not too fat for conversion. Go for it. How much does the original engine weight including all the liquids? You might end up with lower weight car than the original was after conversion.

Regarding batteries, I'd say go lithium way. You'll barely meet your range goals if using lead (40 miles max). Lead will end up being more expensive, its really heavy and their performance (and your max range) will get lower the more you drive. If using lithium you'd need to spend that 5k$ on batteries alone to get 40 mile range with acceptable acceleration. But no need for suspension upgrades. Continous power from batteries will be something like 40-50kW but it will move your car just fine. All the torque your motor can provide will be available right at lowest possible rpm. Depending on choice of motor and pack voltage you will do 60 mph easily. Accelerating to that speed won't happen as fast as with original engine. It could happen even faster but that requires more power output from your battery pack.

5k$ on all the other stuff might not be enough. Quick calculation and estimation of prices for main components: controller 2k$, motor 2-3k$ and charger + bms for batteries ~1k$. Those alone seem to blow the budget. Using forklift motor and cheaper motor controller (even DIY/kit) can save you 2k$ easily.

Keeping auto transmission and power everything (accessories) should be no problem.


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## drgrieve (Apr 14, 2011)

You will need to decide if you are going to do a budget conversion with parts you can scrounge or put together yourself by investing double or triple the time to build as opposed to spending like a druken sailor.

The good part about investing in decent parts is that for any future conversions (say car is damaged) you just shift the parts over with no compromises.

For a heavy car on a smaller budget but with good quality parts and a ~50 mile range but still better than ICE performance I would use

Motor - Kostov 11 250v (or upgrade to warp 11 hv 288v) ~$2500
Contoller - Soliton 1 ~$3000 (support auto transmission with idle function)
Batteries - 270 A123 20ah in 3p90s configuration ~$5000

Plus charger, adapter plate, auto transmission work, cables, battery boxes etc etc

Choose a quality motor and controller first get those working and tested in the car with some spare lead acid batteries and move on from there with the rest.

If you can't afford to spend like a druken sailor then that is OK you will need to compromise, spend your time in scrounging parts and building electronic kits. You can save many thousand that way (but the saving comes at a quality & time cost). But you can't save on the battery cost. Usually people spend $8 to 10k so with using the A123 I've saved you as much as you can currently.


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## ChaseDE (Feb 16, 2012)

thanks for the info drgrieve. i found the controller and motor easily enough. what about the batteries and the config of them. 

Batteries - 270 A123 20ah in 3p90s configuration ~$5000


where is a good place to find these batteries and i am guessing 3p90 is a member here? or am i noobing it up?


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## mora (Nov 11, 2009)

ChaseDE said:


> i am guessing 3p90 is a member here? or am i noobing it up?


3P90S means there will be 3 cells in paraller and 90 in series. 3x 20Ah cells in paraller means 60Ah total and 90 of those in series means 288V. 288V x 60Ah results in ~17kWh. If those cells have 10C peak then your peak output from the pack will be something like 150kW.


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## ChaseDE (Feb 16, 2012)

mora said:


> 3P90S means there will be 3 cells in paraller and 90 in series. 3x 20Ah cells in paraller means 60Ah total and 90 of those in series means 288V. 288V x 60Ah results in ~17kWh. If those cells have 10C peak then your peak output from the pack will be something like 150kW.



good stuff mora, thank you


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## drgrieve (Apr 14, 2011)

For more information on A123 cells have a look on this site and jack rickard evtv. Note these cells are very powerful, I'm planning on running them at 15C but are difficult to assemble. 
Alternatively for a much easier build, look at Calb 100ah cells. At 8C max (and a lot more voltage sag) you get half the resulting power from a small 17kwH pack (110 kw) instead of 230 kw. Those figures include voltage sag. Multiply by .8 to get approximate shaft power. However of course at a rough guess multiply by 1.4 to compare to an average ICE car for that low end torque this is for the 0-60. Less advantage over the quarter mile.

Of course you don't need 230 kw motor input, I drive a almost as heavy ICE car that used to make 85 kw (probably a lot less now that's it is 15 years old) with useless low end torque. It is fine. So the Calb option is a still powerful and more practical choice. Price is a little more.

For example 52s 100ah calb cells ~6500.
I would match that with
Soliton 1 ~$3000
Warp 9 ~2000

So around the same price and you'll end up with less speeding tickets and a faster time to build.


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