DIY Electric Car Forums banner
1 - 20 of 45 Posts

·
Registered
Joined
·
72 Posts
Discussion Starter · #1 ·
I am preparing to convert my 1986 Winnebago LeSharo into an all electric vehicle. I hope to complete this and take it on an extensive cross country road trip this Winter of 2018.



I have been building my electronics skills up to this project, tinkering with batteries and go-karts over the last 8 months. I am hoping to ask for some support from all the people on this forum, with your experience and knowledge! I would like to explain my planned approach and am inviting any and all feedback about how I might be able to improve upon this plan.



I am hoping to find a reasonably priced 2016 or later Nissan Leaf SV for salvage with a smashed up body but working guts. (Suggestions beyond Copart for where to look for this?) The Nissan leaf has a motor rated at 107 hp -- the LeSharo has a 100 hp Renault engine. The Nissan Leaf has a GVWR of 4,431 lbs -- the LeSharo has a GVWR of 5,830 lbs (as close as I can tell, though this may not be exact for my model.) The 2016 Leaf SV has a range of 100 mi. I am hoping to achieve a range of 50-70 miles with a top speed of 50 mph.



Does this seem like a good fit for this conversion? Does anyone have any potentially better or entirely different suggestions to consider for how to proceed?



Some questions I am wondering are. . .

Is there a way I can bypass the 3-speed automatic transmission and hook the electric motor straight up to the drive-train? Or would this be ill-advised? Mainly I would like to remove as many clunky and unreliable parts as possible. . .



Are there any resources for how to break-down a Nissan Leaf and get all the goodies out of it?


Is it possible to salvage the HUD screen and computer system from the Leaf and use it in the LeSharo?



Am I going to run into any brake master cylinder issues, or any other systems that might be tied into the petrol motor?



More thoughts and background, for those who are still interested to read-on ;)



My inspiration for doing this conversion is many-fold. I feel the desperate need to eliminate the petrol addiction from my own life. I have often wanted to make a small RV my daily driver, as it has an appeal of "always carrying my home on my back," and also, that it would be more fun for my kids and family to have an open free space to enjoy and interact while we drive for groceries, etc. The LeSharo is one of the more efficient RVs out there, with a decent aerodynamic profile, and a fuel economy of 17-18 mpg. I've really enjoyed this LeSharo so far, but I don't trust the aluminum french engine for a long cross country trip. There's only 1 place to order parts, and the thought be being stuck in a podunk town at the mercy of a chevy/ford mechanic while I wait for a part in the mail is not appealing. . .



I also intend to put solar panels on the roof of this vehicle. It just seems reasonable to me that there should be solar panels on an electric vehicle with such a large roof. I intend to include a simple and lightweight system for being able to tilt the panels when parked to better catch what sun is available.



I would most love and appreciate any comments, thoughts, suggestions, encouragements, or warnings that you all might have!



Looking forward to sharing this journey with such an amazing community~


~Sean
 

·
Registered
Joined
·
72 Posts
Discussion Starter · #6 ·
If you're satisfied with the performance of the LeSharo, I expect that the Leaf powertrain would work for you.

The difference in Gross Vehicle Weight Rating (GVWR) isn't an issue, because GVWR is mostly about structure and suspension, and you wouldn't be using either of those from the Leaf.

A bigger issue would be the Gross Combination Weight Rating (GCWR), and the total loaded weight of the motorhome plus anything it is towing. This indicates how much load the powertrain can haul around. The Leaf's GCWR may not be much higher than its GVWR, and may be overloaded under the sustained heavy load of moving the motorhome.

Between size and shape the LeSharo probably has enough drag to make more of an energy consumption (and thus range) difference than that... but we're all just taking educated guesses.

Thank you for all this information Brian! Thank you for clarifying some of this terminology also. . . I was having some trouble finding the GCWR for both the Leaf and the LeSharo. I couldn't even find the curb weight for the LeSharo. I'm noticing that while the GVWR of the Leaf is 4,430 lbs, the curb wight is only 3,340 lbs, which is not terribly encouraging. But I did find this article:
http://www.mynissanleaf.com/viewtopic.php?t=19293
Which leads me to believe that the Leaf should be quite comfortable towing up to 2,500 lbs beyond it's own weight. I'm hoping that after stripping down the LeSharo as much as I can, it wouldn't be too bad for the Leaf drive train. And indeed, I've been happy with the performance of the 100 hp Renault motor on this vehicle. . . though I wouldn't trust it for tremendous longevity.



You bring up a good point about the drag too. As much as the LeSharo is a reasonable aerodynamic profile for an RV. . . I'm sure it's drag coefficient is still way higher than the Leaf ;) I am prepared to beef up the battery pack if need be to achieve a 50-70 mi range. I have been strongly considering building large battery packs out of 18650 batteries, Tesla style, but way cheaper to DIY.



Btw. . . I would love to find a salvaged Tesla in my price range for this project. But I don't think it's going to happen ;)
 

·
Registered
Joined
·
72 Posts
Discussion Starter · #7 · (Edited)
The LeSharo has a first-generation Renault Trafic powertrain, which is front-wheel-drive, with the engine longitudinally oriented and placed ahead of the front axle line. The Nissan Leaf is an electric version of their common compact cars, and follows the pattern of the engine installation, with a transverse motor placement just ahead of the axle line.

I wouldn't even consider using the Renault transmission. An automatic seems like more trouble to deal with than it is worth. It might be possible to swap in a manual Renault transmission, but it's not like there are a lot Renault anything in North America, especially with that longitudinal layout with the engine overhanging the front. Audi used the same format for many years (and some VW versions of the same cars), so there might be a possibility there. You could even use the transaxle of an air-cooled VW, as long as you use a strong version, and one that can flip to the engine/motor ahead of the axle.

Since both the Trafic/LeSharo and the Leaf are front wheel drive, that suggests the possibility of using the complete Leaf drive unit (inverter, motor, and reduction gearbox with final drive) to replace both the Renault engine and the Renault transaxle. Unfortunately, the Renault is longitudinal (a configuration which was popular for early front-wheel-drive cars, especially from Europe), and the Leaf is transverse (like the vast majority of modern front-wheel-drive cars), so the Leaf unit might not fit well in the engine compartment, and certainly some significant construction of mounting brackets would be required. It can be done, and would be easier than the conversion to a transverse Pontiac engine that I ran across.

Whatever gearing bits are used, the Leaf motor will need a reduction ratio of at least 7:1 from motor speed to axle speed to work properly.

This transverse vs longitudinal issue is one I had not considered! I'm having trouble finding information on the internet about specs/dimensions on the EM61 motor in the Leaf, which makes it hard to determine if it will fit in it's original orientation. I plan to work with a metal fabricator who has done a lot of engine swaps on this project. I know enough to tinker with some electronics and wiring, but I know I would do a sub-par job for welding/mounting/sprockets etc. . . so I'm going to enlist some strong professional help in this department. I'm hoping he can find a creative way to fit the longitudinal leaf drive train into this engine compartment.



Lots of good suggestions here for how to proceed with the gear-box, and I also appreciate the tip about the 7:1 ratio for the leaf motor. A lot of these sound viable, but I agree with you using the whole drive-train from the leaf sounds like the most attractive option. I would be slightly more concerned with the constant overweighting of the gear-box than the electric motor. . . but with the trend towards over-engineering these days. . . I think it might be OK?
 

·
Registered
Joined
·
72 Posts
Discussion Starter · #8 ·
The LeSharo's brake booster will presumably need vacuum, although there was a diesel version which would have had some other boost source. You can add a vacuum pump, but another solution is to replace the entire brake master cylinder and booster with the equivalent from the Leaf, which is electrically powered.

The air conditioner (if you have one) will be run by the engine. If the RV part has a 120 V AC powered air conditioner, it might make more sense to use an inverter to run that rather than to make the Renault air conditioning work on electricity.

Good heads up on the brake booster. I'll have to explore and decide if I want to stick with the LeSharo brake system of switch out to the Leaf. If I use the Leaf system. . . would I have to do this for both front and backs? Seems like it might be more simple to keep the existing brakes and add the vacuum pump. . . ?



We don't use the AC. Though we will probably get a 120V inverter for charging phones and such~
 

·
Registered
Joined
·
72 Posts
Discussion Starter · #9 ·
Solar panels are good for any RV that camps without a powered campsite. Tilting panels does help, if you can position the motorhome to be able to use the tilt (most only tilt side-to-side, not front-to-back).

The solar system will extend how long you can camp without needing to move or to run a generator. It won't collect enough to make a meaningful difference to driving the vehicle.

I'm thinking of building some custom mounting brackets that would allow me to tilt the panels in all four directions. (Though I haven't worked out all the details on this yet~) This way we can get the sweet parking spot with the good view out the back dinette, as well as capture decent sun.



This video was one of the main inspirations for me on this project:

https://www.youtube.com/watch?v=fGZ1zbqAGA0


He says he's getting about a 50 mile range just off of a full-day charge on the solar panels on his VW bus. I don't expect I would get that on the LeSharo, but I'm hoping that I would be able to get a full charge after 3-7 days of camping. In the video he describes how he's loosing probably 10% of this solar energy to heat build-up in his voltage boosters. . . He's only having to boost up to 144V, and I'd have to boost all the way up to 360V. . . so I will need to research more.



Do you think it might make sense for me, maybe even be more cost effective, to find a lower voltage motor, and build batteries from scratch? I was mainly leaning towards using the Leaf because it seemed like the most bang-for-buck to get all the EV components in one quick go~ I'm not familiar enough with the salvage market to know what price is reasonable to expect for a Leaf with all functional components and a banged up body~:confused:
 

·
Registered
Joined
·
72 Posts
Discussion Starter · #19 ·
Having taken apart a crashed Nissan Leaf, I think that it's drive train, power electronics, and battery are better than just about anything you can put together yourself, and certainly cheaper on the salvage market than anything you can assemble from purchased components.


BUT, if you are going to make use of them, you really have to commit to using the whole package. Motor/inverter/charger / battery, computers AND WIRING HARNESS, and transplant the whole thing to your project.


Would it be possible to cut out the entire front drivetrain and just transplant the entire Leaf drivetrain (including wheels/brakes etc) into the LeSharo (what is the distance between the front tires in comparison to the Leaf?)? If that doesn't work, perhaps you could have a custom axle made that would allow the LeSharo front wheels to mate up directly to the Leaf gearbox.


If you go with a different motor, you will have to also buy a controller to match it, and at that point you may be able to use the Leaf Battery (either at a matching voltage, or reconfigured to a lower voltage. If you go 400 volts you may be able to use the Leaf BMS, otherwise, if you reconfigure the modules, you'll also need to provide a bms.) I can't imagine this would be more cost effective than using all parts from a Leaf donor car.

So many good comments here! I wish I knew how to quote more than one person in a post :D


Summetj, yes! Exactly~ I have been thinking about this more, realizing it would be easier to take as many Leaf components together as I can since they are already built/designed to work well with each other. It's kind of a crazy idea, but I'm starting to imagine doing a cut-away style Leaf-LeSharo cross-over. Basically cutting the back end off of the Leaf, and fitting it up inside the front-end of the LeSharo. I've been taking measurements and I think it might actually fit pretty well! I can't wait to get the two vehicles side-by-side with a nice measuring tape :p



I am thinking I will have to roughly double or triple the capacity of the batteries to have an effective cross country EV (ERV?) I am excited at the challenge/opportunity to build some custom 18650 battery packs which would fit nicely under the LeSharo.



I understand all your comments about the Solar being pointless. There is something extremely comforting and relaxing about the idea that I could mis-plan my route, miss a charge point or something. . . and all I have to do is sit there for a week and I could travel another 20-30 miles to reach the charge destination. It's like an EV cross-country safety-net. . . maybe not worth all the weight and drag . . . I get it. I'll think about it more and crunch some more numbers. . . I could easily fit 5 (6 if I was pushing it) 300W panels on the LeSharo, bringing it to 1,500W. Am I doing my math wrong, that this would be about 1/5 of a 6.7kw charging station? So say it takes me 12 hours to charge up to full at a station, it might take 60 hours of full sun, or 10 days (in good conditions) to fully charge by solar? It just seems like after a week of camping (not using the panels for any fridge/cooking etc. . . ) that I would be able to go . . . you know. . . somewhere???
 

·
Registered
Joined
·
72 Posts
Discussion Starter · #20 ·
GCWR is often hard to find for vehicles which are not expected to tow very much, and especially for those for which towing is not recommended at all.


It's good that the performance was acceptable, and the stability and structural questions won't matter to the LeSharo, but I would be a little cautious about the long-term reliability under substantial load. Presumably the motor and electronics would be protected by power reduction triggered by excessively high temperature, but the battery doesn't have active thermal management.


All the stuff in an RV costs the manufacturer something to put there, so there usually isn't much of anything extra. Rather than just removing anything, there are sometimes lighter (and more expensive, which is why the RV manufacturer didn't use them) alternatives. Go for lighter weight, but keep your expectations low.
Without really watching the video (although I did later fast-forward through it), if 50 miles requires 15 kWh of energy stored in the battery, that suggests a 2000 watt (peak) solar array, and full sun exposure. That's 20 square metres (or square yards) or so of panels, or at least far more than what fits on a VW van. So, what were his power and energy numbers?

It seems unlikely to me that there would be a great benefit to a lower system voltage, just due to more efficient voltage conversion, but this is not my area of expertise.

There are certainly lower voltage motors, but you can still use Leaf (or Chev Volt, or whatever) modules for the lower voltage - just use fewer modules in series.

Brian, your comments are so awesome! Really helpful for a new guy like me~


I'm amazed that the Leaf does not have an active thermal management system. I've been considering fixing some heat-sinks onto the additional battery packs I will add to have the wind under the vehicle help to pull away heat from the batteries. Is it reasonable to assume that if I double or triple-up the battery from the original Leaf, that the strain (and heat) on the original battery would be lessened?



By "stripping down" the LeSharo, I am referring to the obvious stuff like gas-tank, exhaust system, etc. Though I have been thinking about removing some of the internal stuff we don't use, like the TV antenna and the lieu ;)


Does anyone have any links to specific specs on the EM57 in the newer Leaf's? Things like acceptable input voltage rage, etc, I'm having trouble finding any detailed specs on this motor. . .
 

·
Registered
Joined
·
72 Posts
Discussion Starter · #22 · (Edited)
The Leaf has optional battery heaters for use in cold climates.

I doubt this would help very much because each battery module has a lot of thermal mass and I don't see anyway of removing the heat easily.

Hey, thank you for your comment Kevin. I could be way off here, but isn't that exactly what a heat-sink is for? When you have some thermal mass with heat building up inside of it, a heat-sink can be used to remove the heat more quickly from the mass ~ just like in a CPU or GPU, which is where I'm familiar with them. The idea is to get the mass and heat in good contact with the heat-sink so the heat transfers to the sink. Then the sink is designed with a lot of surface area so that air flow is more effective at removing that heat.

I haven't gotten deep in my battery size calculations yet. . . (exactly how many 18650's can I fit under my LeSharo? ~ more on that later) . . . so I'm not sure exactly how much covering the battery box in heat-sinks would cost. . . but it's looking really expensive on Amazon. Might have to talk to my fabricator about working it into the aluminum battery box. . . But yes, I have doubt's about whether it's worth it!


It's difficult to quantify the impact although I guess if you're drawing half the current then we would expect a reduction in heat build up.

I'm hoping so ~ and hoping in general that spreading the load across several batteries would reduce the wear and tear on the system from constantly handling a larger load than it was designed for.

Can anyone with more battery knowledge chime in? If I spread the same motor-draw across two batteries in parallel, each providing the same voltage, would this reduce amp-draw on each of the two batteries individually? Does it cut the amp-draw in half? (or close to it?) Finally, would this also reduce heat build-up?

Note that the latest 40kW Leafs overheat much more readily than the 24kW/30kW Leafs. You may want to factor that into your battery choice if you're convinced you have a problem with heat.

That is a very good thing to know! I will keep this in mind when selecting an auction vehicle~
 

·
Registered
Joined
·
72 Posts
Discussion Starter · #25 ·
If you have a look at the Leaf battery module construction (see here) you'll see that no attempt is made to remove heat from the pouch cells. Therefore unless you're going to repackage the pouch cells with a heatsink I do not believe you will have any significant impact using a heatsink at the module level.

My advice is to run the Leaf modules as designed without cooling or use Volt/Tesla modules that have integrated liquid cooling if you are convinced heating is a problem.
I have seen cut-away images of the Leaf drawing heat away from the batteries and pumping it into the passenger compartment for added comfort heating. Is this only on later models? I was not sure if perhaps they had a way to divert that heat outside of the vehicle as well? I totally agree I would not want to modify the existing leaf battery~ Their system is working well enough. Can you confirm/clarify that the Leaf (even newer ones?) don't use any liquid cooling?



Don't bother trying to build your own 18650 based pack. Tesla and Volt modules are much cheaper and safer.

I have been wondering about this. It looks to me like a complete Tesla module cost break-down is . . . hard to determine. I'm seeing on eBay, a 90kWh 24V module for $700, and also a 4.5 kWh 24V module for $1250. I did some rough math and I'm guessing that I could spot-weld my own pack for about $1500 in materials that would be equivalent to the Leaf pack. This would be without a BMS. . . which I know sounds crazy, but I have been wishfully (foolishly?) thinking that since this pack would draw half (or a third, if I use 3 packs) of the amps that the Leaf originally drew from it's single pack, and if I was conscious to add some sort of heat-sink, that I would probably be safe from any overheat in my custom pack. Please talk me out of my insane idea.
 

·
Registered
Joined
·
72 Posts
Discussion Starter · #26 ·
My wife and I have a bad (but oh so good) habit of off-roading just a little bit in our RV to get off the beaten path for some good boon-docking. I have been considering raising up the leaf suspension in the back of the LeSharo and adding duelies on the back to accommodate the weight of additional battery packs, and also to support our bad habits :D


Does anyone have any experience or knowledge about what would be required to raise the front suspension of the Leaf? Also, I'm thinking it would be prudent to replace the wheels on the Leaf with the front wheels from the LeSharo, for the weight rating on the bearings and also the tires.



Any thoughts on this?
 

·
Registered
Joined
·
72 Posts
Discussion Starter · #27 ·
Think of batteries like a jug full of water.

Think of power as the rate at which water leaves the spigot on the jug.

So, two packs will be exactly half the power draw.

Lithium Ion batteries (and probably all batteries) deteriorate with age and use, so if you use them less aggressively, they'll last a bit longer.

If you use two packs that were each built to be sufficient on their own, you'll also see a very small (fraction of 1%) improvement in efficiency due to 1/4 as much heat loss in wires. But this would be equivalent to just beefing up the wires on a single pack, so, not much to gain there.

Thank you Matt! This is exactly what I'm looking for~ Any thoughts on the functionality/practicality of adding an air-cooling heat-sink to a custom designed battery pack? Not for the leaf battery, which I would probably leave untouched. . . but for a new custom pack or two that I might build?
 

·
Registered
Joined
·
72 Posts
Discussion Starter · #31 · (Edited)
Hey AwesomeMatt,

I appreciate the comments about cooling the battery packs. I think you're spot-on!

Doing some deeper math and giving it more consideration, I now see what everyone is saying about getting prefabbed EV modules.

Kevin, do you have any experience or preference working with the Tesla modules, or Volt, or something else? Are the 5.3 kWh, 24v Tesla packs the best way to go?

I'm a little confused about working with these 24v Tesla modules. . . I would need 15 or 16 of them in series to get to the 380 volts that the Leaf operates at. . . crazy expensive! And then the Ah of the pack would be way bigger than the Leaf. . . seems like maybe not the best fit?

Would it be better to just go with the Leaf modules? 7.6V, 64Ah * 50 would get me pretty close at 380V and 24kWh. Pricing on this looks like about $5k~

I'm amazed that just the price of an equivalent 30kWh battery module is about the same price as an entire used Leaf! :confused:
 

·
Registered
Joined
·
72 Posts
Discussion Starter · #32 ·
There is something I'm wondering about as I am thinking of doubling up the batteries from two different leafs. What would happen if I paired a 24kWh Leaf battery in parallel with with a 30kWh Leaf battery? Would they end up draining differently? Wearing differently? Charging differently? Is this a terrible idea? Or could it possibly work out alright?

There are a limited number of options when looking at salvage auctions so I am wondering if it might be alright to run two similar, but not identical, batteries in parallel~

Would appreciate any thoughts or feedback!

One more question. . . if I reduced the 1:7 gear ratio standard on the Leaf even further, thus lowering the top-speed, might this potentially be a better fit for a heavier vehicle like this? I've read that the Leaf has a top speed of 93 mph. I'm even considering putting two Leaf gear-boxes in series, thus rendering the top speed of the vehicle to 45 mph. . . but would this also help to relieve some strain from each gear-box, and possibly also reduce the torque required by the motor? Or reduce the wear and tear on the motor? We're not trying to get anywhere fast ;)
 

·
Registered
Joined
·
72 Posts
Discussion Starter · #35 ·
Unmatched battery packs would be a discharge and recharge nightmare to get to function properly and safely.

You need to do more homework on power transmission and gear ratios. Combining gear ratios in series multiplies the overall ratio. It does not add them. Two Leaf gear boxes in series would give 1:7 X 1:7= 1:49 not, 1:14. Think of 7 input rotations giving 1 output rotation from the first box. 7 of those rotations givies one rotation from the second box. 7 X 7=49.

You are right! I should do at least a tiny-bit of homework before I start saying my crazy ideas out loud :p. I can't help it. . . visionary mentallity. 10,000 new ideas/day ~ most of them highly impractical. :rolleyes: I haven't worked with gears much before so I am not that familiar with them. But I now understand the concept you are describing~ if I wanted to go from a 1:7 ratio to a 1:14, I would only need to add a 1:2 ratio gear. So . . . is the rest of my theory sound? If I have a heavier vehicle, and I don't mind if the top speed is slower, would it make less strain on the motor to gear it down a little further? For all practicality and simplicity, I will probably just leave well enough alone with the standard Leaf gear-box. . . but I was just curious if I am thinking about gear-theory correctly~


Also, thank you for clarifying about mis-matched batteries! I assumed as much, but was having wishful thinking. . . I will make sure to get a second Leaf who's battery matches my first. ie: if I get a 24kWh pack, I will make sure the second pack is also 24kWh.
 

·
Registered
Joined
·
72 Posts
Discussion Starter · #36 ·
The Leaf modules are a good solution if you can live with the lack of cooling (which works fine in the Leaf). The best way to buy them is in a wrecked Leaf which will also have all the other parts you need :)
I have come to the same conclusion. Salvaging the battery pack from a wrecked Leaf is going to be the cheapest route~ Now I just need to find two of them with the same type of battery!

On a related note. . . I am strongly looking at a particular salvage Leaf with a smashed up trunk. I had an inspector go look at it for me and he said it looked like a light accident that only had body damage in the rear; however, he also said it won't go into gear. He postulated this was because the Leaf has an open-trunk sensor which would prevent it from shifting into gear. Anyone know about this. . . ?

Also, are there other safety systems that I will have to somehow disable in order to make the Leaf run normally after I chop-off the back half of the vehicle? Will this be workable, or substantially complicated?
 

·
Registered
Joined
·
72 Posts
Discussion Starter · #40 ·
They're not really 24 volt. People seem to want battery systems to run at some multiple of 12 volts, but it doesn't work that way. Tesla Model S/X modules have 6 cell groups in series... which is 22.5 volts for the module at 3.75 V/cell (nominal).

Yes! This makes much more sense. I think a lot of people are using these Tesla packs for DIY Power Walls and off-grid applications ~ so they are probably used to working with lead-acid.


Lower-capacity Tesla Model S/X batteries had 14 modules in series; larger (100 kWh and I think 85 kWh) batteries have 16 modules in series. Yes, since (like all modern EVs) all modules are connected to each other in series, large battery capacity means that you can't use the stock modules to build a low-capacity high-voltage battery. As Kevin mentioned, some companies do modify the Model S/X modules to 12s, cutting the number of modules for a given voltage in half.

This brings up another point I've been wondering about. The Leaf Motor (EM61) operates at 380V. What happens if I power this motor with a lower voltage battery? Say I used 12s Tesla packs and ended up with about 270 Volts? What if I got really crazy and went to 150V?



The Motor would have less power?
The Motor would get hotter?
The stock wiring would not be capable of handling the current?


I've been realizing that while 100hp petrol engine in the LeSharo is probably "under-powered," I barely ever use the full power of this engine. I would say 80% of the time I'm only using 30% of the available power. The only time I might use close to full-power is when climbing a steep hill.



This makes me wonder more crazy things. What if I used a lower power EV motor, (or wired the EM61 at a lower voltage?) and included a voltage ramper to give shorter bursts of higher power. I know there are a lot of circuits/products available out there to change voltage up or down pretty easily. I know these components get hot. Would it be possible to use one of these to provide a temporary "boost" by ramping up battery voltage for a short time?
 

·
Registered
Joined
·
72 Posts
Discussion Starter · #41 ·
Budgeting time!

I was originally hoping that I could complete this cut-away project for under $12,000. . . I'm now seeing that this is wishful thinking! Let me break my estimates down. . .

Main Salvage Leaf - $9,000
Secondary Leaf for just the battery pack - $5,000 (after selling off other components on eBay)
Fabrication and mounting work: $4,000

I'm not even listing an "extraneous" column and I'm already at $18k. . . way over budget.

This is the most cost-effective route I can think of to achieve this LeSharo EV conversion. . . I have been brain storming everything I can think of, including building from scratch components with god-forsaken lead-acid batteries, and this Leaf-Sharo still seems to be the best route for both functionality and cost. Therefore, I am thinking I may have to slow this project down. . . probably not complete it by this Winter :(, and just watch and learn the Salvage market better and keep an eye out for smokin' Leaf deals. . .

Any other thoughts about this?

I've been using Copart salvage auctions. I was appalled when I realized how much their members fees are! After fees and taxes a bid that ends at $7,500 ends up costing $9,500 to pick-up from the lot. And that's if it doesn't need to be shipped!

Anyone have any recommendations for better (or just more?) places to find salvaged Leafs?

Can anyone give me hope!?
 

·
Registered
Joined
·
72 Posts
Discussion Starter · #43 ·
You could use two of those in series. $500.

Ok, I'm gonna have to play with this!

https://www.youtube.com/watch?v=tJqN9qADajM


Any resources/suggestions where I can learn more about running two DC motors in series?



There are Volt packs available for $1000 for the whole car's worth. Not sure where you are, but, that's how I'd go. I wouldn't rip the car apart myself unless I thought it was interesting or fun or I was extremely thrifty.
I'm located in MN. Not a ton of EV popularity up here. People seem to think they wouldn't work well in the cold, but the few local owners I've talked to say they work just fine~


Where are you finding a whole 380V 24kWh pack for $1000??? Pricing it out on eBay, I usually see a single cell (7.6V, 64AH) for about $100, which comes out to your $10k for 2 complete Leaf batteries for my project. But are you really finding them for $1k each, for a whole pack?? That price would definitely make my project a go ;)


There is no equilibrium where lead-acids make sense. They are universally worse and more expensive. It's not a shortcut, it's not a "Well I'm cheap and I'll accept lower performance", even if you want to cut corners and accept lower performance, just go with fewer lithiums, it's still better. It's better in every way.

Sage advice. Worthy of Obi-Wan.
 

·
Registered
Joined
·
72 Posts
Discussion Starter · #51 ·
Jack at EVTV has a couple of dual motor setups on his website (here) :cool:
That is a wild picture! I have often wondered about this. . . running two motors in a mechanical series. . . I am not certain I understand exactly what is going on in this photo, but I am wanting to understand more!

Feeling so much support from this forum! So many good comments ~ I'm deeply appreciating the help spreading this knowledge~

As I have mentioned, we have a habit of off-roading with our RV, and I have oft-wondered about turning it into a 4WD. This video was inspiring to me:
https://www.youtube.com/watch?v=3ZHCrXu3vus

He's proposing that wiring DC motors in electrical series might be an effective solution for a sort-of built-in traction control in a 4WD application. He states P = V * R^2. If one wheel suddenly lost traction, it's resistance would drop dramatically, and then the other wheels would take-up all that extra ampereage/power. Any thoughts on if this principle might work?

I got all excited imagining a set-up with 4 small DC motors, one on each wheel . . . . then I realized it would be a steering and suspension nightmare :D.

Might it be remotely sane to consider having two forklift motors as you have mentioned, one in place of the old petrol motor, driving the front wheels, and the second driving the back axle. Imagining differential issues in the rear wheels might prevent this from being practical for most road driving? Maybe one motor in the front and two in the back, one for each wheel?

I will look more deeply into running the motors in mechanical series.

I'm watching the salvage auctions. Made a few bids today, but didn't win. 2011 International eStar, and also a 2017 Bolt. (Anyone have word about these 60kWh Chevy batteries being decent or not?)

I'm sure this is a common question but. . . is it easy enough to implement regenerative breaking with a forklift motor? I really like the idea of having the car handle like the Tesla's do . . . where as soon as you let off the accelerator, it starts heavily regen-breaking. Does it just depend on how I configure my speed controller, as Mr. Damien Maguire would have me build from near scratch? :p
 
1 - 20 of 45 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top