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Discussion Starter #1
Hello! I am ready to start work my first EV conversion.
This build will be low budget, and where possible from used or home made components.

I have a reasonably well equipped workshop set up here, including Several lathes mill and shaper.
I have not decided on a project vehicle or exactly what batteries motor controller/ charging set up i will use.
I am here to learn, and share any knowledge i have to help others if i can.

I am flexible on what and how i build this first EV, but one thing is set in stone, it will be low budget and as much as possible produced here at home.

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Welcome to the forum,

I like the idea of promoting budget builds, it's very easy for the costs of these projects to run away with you, but there is an ever increasing supply of components out there as people figure out ways to control the different OE inverters and motors.

I am pretty sure there has been a lot of work done recently on the less exotic components (i.e. not Tesla) that can offer very good value for money, e.g. Prius Gen2 inverters and Lexus gearboxes and differentials.

This also seems to be a growing scene here in the UK, so great to see more people taking up the challenge.

Good luck!
 

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Discussion Starter #3 (Edited)
Welcome to the forum,

I like the idea of promoting budget builds, it's very easy for the costs of these projects to run away with you, but there is an ever increasing supply of components out there as people figure out ways to control the different OE inverters and motors.

I am pretty sure there has been a lot of work done recently on the less exotic components (i.e. not Tesla) that can offer very good value for money, e.g. Prius Gen2 inverters and Lexus gearboxes and differentials.

This also seems to be a growing scene here in the UK, so great to see more people taking up the challenge.

Good luck!
Thank you for the welcome.
I am not Even decided on a car just at the moment, but i do have a fork lift truck lined up, via a mate of mine.
It is complete and I can have it dropped off at mine, strip what i want out of it and he scraps what is left.
I have a Volvo car i am ready to scrap, and this will be Effectively payment for the fork lift Gear.
So its looking life a START, of some kind if it all Comes to fruition.


I am Totally Green on Forklifts or EVs, My sum total knowledge is from the string of videos on youtube by Benjamin Nelson (EV Metro) and the two mighty car mods EV Purchase/ experiment from a few years ago.
My knowledge of batteries charging and Electronics in general, again is very basic.
But i am no beginner in fabrication or Machine work . I have build many Modified cars over the years and motorcycles. And I love diesels and have been responsible for diesel converting many Old land rovers back in the day. so simple stuff like motor plates and Couplers are of no concern.
Matching this Fork lift motor to a car, is one thing i am in the dark about .
And Car choice has to be what i can find For scrap local to me through friends.
At the moment i have a 2003 sprinter van Low roof MWB, A 2008 seat altea TDI and a 2008 Peugeot 307 Station wagon.

I am thinking the sprinter is way too heavy for the Fork lift motor, but unsure.
The two cars are i think offer a better option, but not sure if i need even smaller lighter car, or if i need a larger car like these to carry the batteries.

My goal is to make an ev, that can provide a reliable 20 mile in total range, and speed is of no importance. 40/45mph will suffice for our requirements.
My plan is to utilise everything i can from the forklift, and improve on things as i gain knowledge or experience.

I have the charger with the forklift If it all goes to plan. AFAIK, the fork lift was working but battries were failing and mast needed work, they purchased A Diesel, and it has just sat there in a derelict building for the pat six months.

My only other criteria is it has to stay AS cheap as it can be, plan is to use lead acid batteries.
Unsure at this time, condition of the forklift batteries exactly, and all i know is there are 8 he could see but cables going to more. OH! and they looked Tall compared to typical car battery.

As you can see my nativity/ Inocence if you like on all things EV conversion is beyond basic.
I am not closed to ideas of Electronic improvements, but it will have to be Mostly DIY.
 

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Unless you've got a source of almost-free lead-acids, I'd skip that step entirely... 20 miles isn't a long range, so you won't need to break the bank to get a lithium pack for that (depending on the vehicle - a 20mile range sprinter is going to need a lot more batteries than a 20mile range hatchback).
 

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Discussion Starter #5 (Edited)
Unless you've got a source of almost-free lead-acids, I'd skip that step entirely... 20 miles isn't a long range, so you won't need to break the bank to get a lithium pack for that (depending on the vehicle - a 20mile range sprinter is going to need a lot more batteries than a 20mile range hatchback).
Appreciated. I kind of guessed that but your confirmation, gives me a direction. Lightweight.

On the subject of batteries, Is it feasible to build Cells from scrap 18650s .
I am not seeing Old leaf cells on ebay uk at what i see as cheap prices. What are the options for cheap light batteries, or are there no such things.
 

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Keep an eye on the classifieds page here, Ebay, Car breakers yards etc.

By far, the best used batteries you'll find are from crashed/scrapped EVs. Since you're aiming for a small pack, maybe look at batteries from recent hybrids too - as these are generally smaller and cheaper. Sometimes new/nearly-new cells crop up at a good price - you just have to keep eyes on everything until they do.

I personally do not much like the idea of using large quantities of scrap 18650s - though it can be done. To me, it seems like a losing battle, trying to parallel so many often wildly unmatched cells. Additionally, it is a lot of work - testing each cell individually, designing a pack from them that safely deals with a given percentage of cells failing outright etc. Larger format cells with less parallel connections will likely give you less trouble overall...

I was trying to track down a Leaf pack but ended up settling on buying a load of cells from a classified ad here and am much happier that way around - but it's always a balancing act.
 

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I am not seeing Old leaf cells on ebay uk at what i see as cheap prices. What are the options for cheap light batteries, or are there no such things.
Minor terminology issue: you won't likely find individual cells from any EV, and they are way too much trouble for most people to work with, anyway. The practical units to work with are modules, which are permanently assembled groups of cells with a case and wiring for the battery management system. The Leaf modules (before the latest Leaf+ variant) are unusually small and simple, containing only four cells each.

Even though you will likely work with salvaged EV modules, the usual way to buy them from a salvage yard is as a complete pack; you disassemble the pack, test each module to check condition, and re-arrange the modules into your desired configuration of pack, with wiring components, thermal management (heating and cooling) provisions, and housing. If you buy individual modules, you are probably paying someone else to do that disassembly and module selection.

There isn't a big difference in weight of EV batteries, for the same energy capacity. The lightest might be half the weight of the heaviest, but even then there are technical trade-offs and simply suspect specifications.

Since you're aiming for a small pack, maybe look at batteries from recent hybrids too - as these are generally smaller and cheaper.
Yes, but only plug-in hybrids (able to be charged from an external power source), because they have enough energy capacity to drive a vehicle at least several kilometres and sometimes up to 50 km; that's typically between 8 kWh and 20 kWh. Non-plug-in hybrids have tiny batteries, as small as one kWh; they're not good for anything much bigger than a child's toy.
 

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You're absolutely right Brian - my omission there...

I guess I've excluded prius-style or low-voltage mild-hybrid cars from my head because I think they're pointless :)
 

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Discussion Starter #9 (Edited)
Today i have decided the start the build, i will start a thread in due course.
I have chosen a base car, decided on practicality small physical size (i want to work on this in a small workshop so not to have to keep moving it to do other vehicles).
It was down to what was available to me local and a Citroen C3 2006 petrol (snapped timing belt) turned up so i went for it.
Not the lightest car around but small five door hatch , that complete weighs around a ton, i will lose 4 cwt perhaps a little more, ditching the petrol engine and equipment.

But i think the first task is once it is mechanical stripped start to get creative with the hole saw and shed weight off the car any where i practically can.
I need it to be a practical car, but removing an unnecessary item, like this car has air con will lose weight.


citroen c3.
 

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But i think the first task is once it is mechanical stripped start to get creative with the hole saw and shed weight off the car any where i practically can.
I need it to be a practical car, but removing an unnecessary item, like this car has air con will lose weight.
Leaving out air conditioning does make sense, if you don't need it, both because it reduces weight and because it removes the need to find a way to drive it, without the engine.

In contrast, the manufacturer of any modern car does not include any significant amount of unnecessary metal. Many engineering hours and millions of computing dollars are spent optimizing body and structure designs, so it you remove enough to make a useful weight difference you will have compromised the car's structure.
 

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Discussion Starter #11
Leaving out air conditioning does make sense, if you don't need it, both because it reduces weight and because it removes the need to find a way to drive it, without the engine.

In contrast, the manufacturer of any modern car does not include any significant amount of unnecessary metal. Many engineering hours and millions of computing dollars are spent optimizing body and structure designs, so it you remove enough to make a useful weight difference you will have compromised the car's structure.
Thank you brian.

I was thinking of leaving the main structure alone with regarding drilling holes, and concentrate on two areas of the car i see as over constructed.
i could remove steel from the bonnet/hood internal structure and the tailgate/hatch and possibly inner door structures.
But on a car this small, i do not know what a difference removing steel in these areas could make to how the car crumples in a collision.

Same with removing weight, how much and where might change the handling characteristics, so i want to try and keep the front/rear weight bias something as it is on the stock car where i practically can.


Here are the euro n cap an other test videos on a 2002/ early c3, the model i have is a 2006, slight styling differences, but structure etc i imagine very similar. other vid shows the sub structure in a unique way. saved me laying on my back. ;)

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c3 2002

https://youtu.be/c-T7cjR8KyE


https://youtu.be/i6SPSVsIg7M


https://youtu.be/Xycr1EXK3tU





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Hi Chief and all,
Glad to here you jumped in, I look forward to reading about you build.

I've gone all in as well, and yesterday put a deposit on a '72 Mini Moke that I intend to convert. I have only just joined the Forum.
 

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Discussion Starter #13
Hi Chief and all,
Glad to here you jumped in, I look forward to reading about you build.

I've gone all in as well, and yesterday put a deposit on a '72 Mini Moke that I intend to convert. I have only just joined the Forum.



The mini is light but, the engine layout with its long crank nose clutch and power sapping transfer gears is one i did not contemplate for these reasons.

Its gearbox once off the engine is open topped and will need a big cover making for it, need not be that heavy duty as you could mount any motor off the transfer case. really any negatives i mentioned here are way out shadowed by the positives the mini brings to this job. Super simple and strong and light nothing not to like.

In my C3 citroen build i got complexities a plenty central locking and all the underdash mess to wade through. i have not even got the engine completely out yet, been stripping the wiring loom down removing heaters air con and making sure i tidy up the lighting and front electric window wiring, its taking a lot longer than i imagined. I am trying to lose every last strand of copper wire i can yet keep what i have to practically leave installed functioning . And yet have tidy wiring going to it.

I am not 100% on the digital speedo yet think its staying but its creating the need to retain loom i would rather loose if i could.

I think i could have been way further forward than i am right now, if i had just tore into it and effectively gutted the thing and started afresh, but i want it to look more or less stock if i can, this takes time.

This engine just a 1.4 litre petrol engine has some huge mountings and big old AC pump etc, its over 10lbs i think nearer to 15, lots to go but just the AC has dumped a good lump off the overall weight . I would like to lose electric windows at the front, rears are wind ups in this model spec. Not sure i can get front wind ups in this model it seems even low spec have windows By electric these days.
 

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Discussion Starter #15
Not so much batteries just yet, but Going to be everything off a scrap forklift. I missed one, but something will turn up.

I want it simple and not ruled out other motors yet, but thinking dc and i am not wanting high power or even long range 40 to 45mph is all i want and a max 15 to mile range is enough for what i want to do.
I Wndered about a big 24 volt lorry alternator but not sure it will drag this big old car around, its too fat needs to lose as much weight as it can, before i get too involved. something will turn up.
 

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Discussion Starter #17
What i am trying to do with this build is not change the dynamics of this car in anyway. i want weight exactly where it is now weighing everything i take off, i even want the brakes to function and feel as stock, and will be using a diesel vac pump for the brake servo off the diesel version of this car.

I want to keep the weight variations back to front proportionate but overall much lighter. Loosing every last thing i can, is my plan but maintaining appearance and all features on the car i want to retain. .

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I want to keep the weight variations back to front proportionate but overall much lighter. Loosing every last thing i can, is my plan but maintaining appearance and all features on the car i want to retain.
I don't think "much lighter" is a realistic expectation for an EV conversion, even with modest range and performance.
 

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Discussion Starter #20
I have Removed the whole heater aircon system, this and the lower dash board area glove box and airbag system has removed in the region of 60lbs. Radio speakers and associated wiring from aircon airbags etc, amounts for about another 15lbs. with nothing having changed much. Removing dash sub structure now unnecessary about 10lbs. It all adds up to just over 70lbs so far. the rear seat back is steel pressing and i think i can lose another 18lbs or so from there. Front power windows are so anoying and not available in wind up versions on this car. You really want a light very basic car to begin with, but i must say ABS dash panels etc are surprisingly heavy, and though your not moving big amounts of weight, it all adds up to a nice weight loss.

The glove box alone for example weighed in about 9lbs with door structure etc.

The bonet catch release is on a steel pressed bracket, that was hiden by the glove box, re sighting that to the upper framework next to brake light switch , made it less visible and removed a piece of exposed steel that weighed in about 2lbs and was a potential knee slasher in a crash, in its unprotected state.
 
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