# VW Polo/Derby -89 conversion plans & making



## mora (Nov 11, 2009)

I'm watching with interest! I'd say it is tough to get 100km range at 144V/100Ah but it might be doable. Even I can get 80km range with tired/random 144V/90Ah Thunderskies in a bit heavier car and without driving too carefully (I mean watching amps, of course, heheh).

How about 160 volt pack? 50 cells in series. Shouldn't blow the budget. If charging voltage is 3.6V per cell then total pack voltage near end of charge will be 180V. Within limits of DC/DC. Soliton should allow motor voltage limit if you want to baby your motor. That means more motor amps over wider rpm range with less battery amps.


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## Ziggythewiz (May 16, 2010)

I'd do at least the 100 AH cells, the less interconnects, the better. As mentioned above, add cells to boost the voltage and range if you can.


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## Tomppa (Jun 30, 2012)

I chose Soliton for it's reliability, easy-to-understandability and all the fancy features, which limiting motor voltage is just one of.

50 x 3.2v x 100ah x 80%DOD = 12,8kWh usable energy. Should be able to travel 100km per charge at *city speeds*. Most of my driving, ~90%, is in the town.

DC-DC's max input voltage is 216v instead of 192v. I remembered that wrong.













If the voltage is 160v, could I use TcCharger 156v charger? How much I loose capacity? 
Charger's nominal is 156v -> 49 cells. 49 x 3.65v = 178,85 pack top voltage.
178,85/50 = 3.577volts per cell. And how does this affect miniBMS, which starts shunting at 3.6v per cell? Charger's end voltage can be customized, but I don't find it worthwhile.

I have 3 Polo transmissions. One still in the car, one at the machinist and this one is just a piece of junk. Ball bearings or/and something else has given up. 














Here you can see how small the Polo tranny is. 0.35l Coke bottle fits barely inside..


Tomi​


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## mora (Nov 11, 2009)

If ordering directly from TCcharger they will customize your desired ending voltage with no additional cost. Prices at GWL Power are very tempting though. I'd say there is no noticeable difference between 3.55V and 3.65V ending voltages. In capacity I mean. It takes like one minute for one 90Ah cell to climb from 3.55V to 3.65V at 10A charge. There is very little charge put into a cell during that time.

But will charge ending voltage affect lifespan or something else inside Sinopoly cells? Like older TS cells like occasional charge to 4.0V. What happens inside the cells if they are always charged to 3.55V? Maybe this could be asked directly from Sinopoly.

If miniBMS shunts at 3.6V then it should be no problem if charging ends at 3.55V per cell. You'll lose no additional energy to shunts. Charger will terminate charge before any shunts even start operating. This is the case with balanced pack. When pack gets unbalanced shunts will take care of cells going too high in voltage. This will happen very near at the end of charging process so charging current has already gone way down.

12800Wh / 100km = 128Wh/km or ~204Wh/mile. That's some serious efficiency in my opinion. But it might still be doable with light car like yours.


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## Ace_bridger (Nov 22, 2011)

Watching with interest while I complete my Golf build.

Will keep an eye on posts and offer adivce where appropriate.

Good luck and well done!!

Adam


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## Tomppa (Jun 30, 2012)

Mora's Golf and Eman Cardona's Fiat have been my main innovators.

Mora,



> Even I can get 80km range with tired/random 144V/90Ah..
> ..12800Wh/100km = 128Wh/km or ~204Wh/mile


144v x 90ah x 80%DOD = 10,368kWh / 80km ~130wh per km. Your wh/km consumption isn't bad either.


> It takes like one minute for one 90Ah cell to climb from 3.55V to 3.65V at 10A charge.


 Oh, that's fast, thanks for the info!

Adam(Ace_Bridger),

Yes! Thank you. I have been following your conversation for awhile. Very neat Golf you have! Loved the video

Tomi

P.s Next week the Polo will have new paintwork


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## mora (Nov 11, 2009)

I haven't measured total energy put back to pack from the wall but I believe DOD was somewhere between 90% and 100%. At 100% DOD that range would yield 162Wh/km but at 90% ~145Wh/km.

But then I got a bit over 60km max range with my 96V/90Ah pack and it calculates as ~137Wh/km. 80% of that distance was done at 80km/h. I have thought that upping voltage improves efficiency very slightly. So yes, ~130Wh/km should be possible.


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## Nomad (May 8, 2009)

mora said:


> I haven't measured total energy put back to pack from the wall but I believe DOD was somewhere between 90% and 100%. At 100% DOD that range would yield 162Wh/km but at 90% ~145Wh/km.
> 
> But then I got a bit over 60km max range with my 96V/90Ah pack and it calculates as ~137Wh/km. 80% of that distance was done at 80km/h. I have thought that upping voltage improves efficiency very slightly. So yes, ~130Wh/km should be possible.


If I could get 130wh that would be amazing!! But ,y crushing speeds are around 65mph


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## mora (Nov 11, 2009)

Yes, power consumption goes way up at 60mph (or ~100km/h).

Regarding 130Wh/km figure: if measured from the wall (total consumption including losses) then 130Wh/km is incredible. My charger is only ~93% efficient at its best. My previous figures (96V/90Ah) did not include charging losses.


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## Tomppa (Jun 30, 2012)

Finally got the car back from the paintshop. In a nutshell: final result was so bad I had to take the car back.The painter was fair and gave me over 60% refund after a short discussion. He had had problems with the hardener and whole car's paint is blurry. There are also small parts unpainted and many drops. We'll see if the paint can be saved with patch painting and pulverizing the paintwork.

The car looks better in pictures but watch the clouds for example...


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## mora (Nov 11, 2009)

Looks like orange peel to me. I'm no expert in painting and don't know what pulverizing is but I managed to take orange peel away by sanding and buffing (factory paint). Even new cars have it but it ain't as bad. Sand using 1500 grit and 2000 grit and then use some Farecla (or some other brand) compound and make it shine. Difference can be seen right after sanding. It takes a lot of time but will be rewarding. Same thing applies to rattle can paints. I've painted some areas of my golf with cheap rattle can paints (with matching color code) and it looks better than original paintwork.

If paint shops would do all this then one full paintjob would be terribly expensive. I'd say even slightest orange peel is almost impossible to avoid but then again I'm no expert in this region, hehe.


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## Tomppa (Jun 30, 2012)

Yes, it's orange peel/skin. Friend's coworker does pulverization in Uusikaupunki. I'm not sure what's the difference between pulverization and sanding/buffing is in practice. Both of them are polishing of the paint. I think it's polishing with even finer pastes than Farecla is.

I have also painted with rattle can paints some areas. Mine doesn't look as good as the original paintwork.


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## Tomppa (Jun 30, 2012)

> Polo's transmission is so tiny that even a K9 won't fit without a little machining. It hits the drive shaft


 Very tight fit








It's 43cm from gearbox axle end to the end of fan. Kptn Chaos has measured the lenght from gearbox to left side of motor compartment in his conversion and it's also 43cm


> The space from the gear box to the left side are 43cm with luck.


I tried to measure it too, got something like 45cm, but it is too inaccurate to rely on (The engine is still in the car).


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## CrazyAl (May 9, 2011)

Tomppa said:


> Finally got the car back from the paintshop. In a nutshell: final result was so bad I had to take the car back.The painter was fair and gave me over 60% refund after a short discussion. He had had problems with the hardener and whole car's paint is blurry. There are also small parts unpainted and many drops. We'll see if the paint can be saved with patch painting and pulverizing the paintwork.
> 
> The car looks better in pictures but watch the clouds for example...


Have you considered getting it vinyl wrapped. I got my EV vinyl wrapped by Funky Car Skins and it came out really good. It attracted a lot of attention at a car show I went to a while back. My wrap has really nice graphics on it as well and is a lot cheaper than air brushing.


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## Tomppa (Jun 30, 2012)

I haven't never heard of vinyl wrapping, thanks for the idea though.


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## CrazyAl (May 9, 2011)

Tomppa said:


> I haven't never heard of vinyl wrapping, thanks for the idea though.


You're welcome


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## Tomppa (Jun 30, 2012)

OK. I have decided which batteries to use in Polo. I'm going to use 49 Thundersky 90ah batteries for a total of 157volts and 90ahs ~14,1kwhs. I asked from a native dealer and got a very good offer. Yes, they are Thundersky and made in 2009 but apparently not much capacity is gone. Dealer is testing them all and I'm going to get them in a two weeks Feels like X-mas is coming.


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## Tomppa (Jun 30, 2012)

I got the 49 TS 90ah batteries awhile ago. The dealer tested every cell and all are still >95ah. Very neat package, 150kg of lithium. 

I'm wondering what the overall peak power will be. Sol Jr can provide 600amps to motor, but will the Kostov 9" 144v be able to handle such a current? Using Franky's EV calculator I found that my max power will be "only" 52kw? I think I can get more power from batteries, but is it the motor which can't handle more than ~50kw?

Next step will be ordering charger + Sol Jr from GWL Power and maybe sometime in winter I'll rent friend's place to finally start the disassembly of Polo


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## dladd (Jun 1, 2011)

Tomppa said:


> I got the 49 TS 90ah batteries awhile ago. The dealer tested every cell and all are still >95ah. Very neat package, 150kg of lithium.
> 
> I'm wondering what the overall peak power will be. Sol Jr can provide 600amps to motor, but will the Kostov 9" 144v be able to handle such a current? Using Franky's EV calculator I found that my max power will be "only" 52kw? I think I can get more power from batteries, but is it the motor which can't handle more than ~50kw?
> 
> Next step will be ordering charger + Sol Jr from GWL Power and maybe sometime in winter I'll rent friend's place to finally start the disassembly of Polo


Looking good, nice find on the used batteries!

I don't think you are going to be wanting to pull more than ~400a out of your cells, so you'll see 600a at the motor for only a very short time at low RPM's. Shouldn't be a problem. The cells would probably be happiest at closer to 300a, which would provide reasonable commuting performance, if not a bit ordinary. I ran at 300a for several months in my car with no problems, but I do admit I like it better at 500a. 

Based on your 90ah cells, and the general desire to keep the extended current draw at 1c, you will probably be a bit limited on the freeway. I know on my car I pull ~100a at 55mph, and ~130a at 65mph. 70mph is closer to 200a. The power requirement climbs quickly with increased speed! I tend to cruise at between 60 and 65mph, which works just fine around here.


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## Tesseract (Sep 27, 2008)

Tomppa said:


> ...Next step will be ordering charger + Sol Jr from GWL Power...


I applaud your choice of controller, but I suggest you get the EMC compliant version sold by Rebbl so that you don't have any problems with registering the car. The EU is really starting to crack down hard on this sort of thing!

Kostov motors already have a CE stamp so you are okay there.


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## mora (Nov 11, 2009)

Don't worry Tess, EMC tests are not needed for cars older than '02 here. Passing inspection is really dependant on inspector himself though. I know at least one of your 1000A controller is being used here in a daily driver and no EMC tests were needed during inspection. Let's hope there regulations don't change.


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## Tesseract (Sep 27, 2008)

mora said:


> Don't worry Tess, EMC tests are not needed for cars older than '02 here. Passing inspection is really dependant on inspector himself though. I know at least one of your 1000A controller is being used here in a daily driver and no EMC tests were needed during inspection. Let's hope there regulations don't change.


Yeah, that sounds like "glaurung" here. Last I heard he was moving his Soliton1 from a Range Rover over to a Jaguar. He hasn't mentioned needing to comply with any EMC rules in any of his posts, so you guys in Finland might still be in the clear on that.

However, my main concern - and the reason I piped in on this thread - is that the EU in general is supposed to be enforcing these EMC rules (most of which can be found here: http://www.autoemc.net/Standards/StandardsMain.htm ) and I really don't want to get another panicky/unhappy email from a European customer who just found out their car can't be registered because the controller doesn't have a CE certification stamp!


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## Tomppa (Jun 30, 2012)

Thanks for your replies.



> Based on your 90ah cells, and the general desire to keep the extended current draw at 1c, you will probably be a bit limited on the freeway.


Here, in Finland, max legit speed is 120km/h (75mph), but nearest area of that speed is 100kms away. So my short trips will be under 100km/h (60mph) speeds most of the time.



> but I suggest you get the EMC compliant version sold by Rebbl


Thanks Tes for you concern. What mora said made me feel a bit better. I even asked Harri (Glaurung) himself and he didn't need any EMC tests/certificates etc on his Range or Jag. So, I think I'm on the safe side with my -89 Polo. 

Some EU regulations really bug me. For instance, agriculture, what is ok in Italy is not ok in northern Finland. Too many differences. But enough of politics!

Here is some pictures of almost done coupler.


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## Tomppa (Jun 30, 2012)

Adapter plate almost done. Only rpm sensor remains to be made.









Here is short video of motor running with gearbox! 
Rpm sensor working


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## Tomppa (Jun 30, 2012)

Okey. It has been a while since my last post. Not much has happened. Just want to share some thoughts.

I want to say that when you consider building of an electric car and think of your budget... Hehe Do realize the fact that you'll get more and more greedy as time goes on. Somebody can be very strict with set limit but I certainly was not.

I had set a sloppy limit of 5k€. Before writing my first post I thought going with Kelly 144v/300a and something like 144v 60ah battery. I don't say that I regret overshooting allmost everything, just pointing out how much it can overshoot if you're not cautious. 

Weather.. It is snowing again and freezing outside, -20 celsius/-4 fahrenheit. I know that lithium battery's voltage should drop in cold environment. I don't understand why my thunderskies still show 3,4v-3,5v as a rest voltage. Is it just the voltage under load that sags more when freezing. Doesn't freeze affect rest voltage as well? 
(FYI those batteries were ~95% SOC, maybe high SOC is the reason?)

Regards, Tomi


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## favguy (May 2, 2008)

Hi Tomi,

Firstly I'm enjoying watching your conversion progress, looking very good so far 

Your voltmeter might be overreading a little bit, so the cell voltages might actually be a bit lower than you think.

Paul


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## Henkka (Jan 7, 2012)

Tomppa said:


> Weather.. It is snowing again and freezing outside, -20 celsius/-4 fahrenheit. I know that lithium battery's voltage should drop in cold environment. I don't understand why my thunderskies still show 3,4v-3,5v as a rest voltage. Is it just the voltage under load that sags more when freezing. Doesn't freeze affect rest voltage as well?
> (FYI those batteries were ~95% SOC, maybe high SOC is the reason?)


Hi Tomppa,

Nice to see that you are progressing. About those low-temp measurements, yes I do think you should measure them under load. Here are few cold-temp "lab" measurements I did few years ago; http://www.sahkoautot.fi/paja:batterytests (and almost same in Finnish, little bit more information here: http://www.sahkoautot.fi/paja:akkumittaukset).

Battery was 72 pcs of TS LFP40 cells and it was frozen at big freezer to about -18C (0F) temperature before tests. Voltage dropped quite a bit when we begun the discharge. As you can see, voltage rose during discharge until to about 0C where it began to drop again. Unfortunately we didn't measure voltage drop with warm cells - should have measured that as a reference point now that I think about it...

Henkka


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## evmetro (Apr 9, 2012)

I am really excited about this build. I had a vw polo gt during the late 80's when I lived in sicily, and absolutely loved it. I don't think I have ever seen a polo here in the states, but if I did, I would buy it in a heartbeat. Then I would convert it. Best of luck on your build.


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## Tomppa (Jun 30, 2012)

> Your voltmeter might be overreading a little bit


My voltmeter is a cheap multimeter and I don't know how accurate it is. Nevertheless, it shows allmost the same readings as in summer. Going to buy a better one.



> Voltage dropped quite a bit when we begun the discharge.


Henkka, your measurements show clearly that voltage sags during discharge and then slowly starts to rise as temperature rises inside the cells aswell. I am certain that if I would put load on my cells they would behave like those in the test. But.. I'm surprised that it seems like freeze have so small effect on rest voltage. That's new info for me

Evmetro, hi and thanks. Pre 90's Polo is a seldom encounter here aswell. Never seen a GT..  Btw. You going to put a Raptor 1200 in a Metro aka Suzuki Swift??? 

Regards, Tomi


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## Tomppa (Jun 30, 2012)

Steady progress. 














I was amazed that it fits very well with the fan.
Next thing to do is the electric motor mount. How have you done it in your fwd cars?


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## jhuebner (Apr 30, 2010)

Hi!

I'm currently converting almost the same car. VW Polo 86C "Kombi"



Tomppa said:


> I was amazed that it fits very well with the fan.
> Next thing to do is the electric motor mount. How have you done it in your fwd cars?


Heres how I did the motor mount








It uses the original "arm" to hold the motor, everything else is straight forward welding.

EDIT: more pics here if you're interested: http://www.diyelectriccar.com/forums/album.php?albumid=226


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## Tomppa (Jun 30, 2012)

Hello jhuebner and thank you for your reply!

I'm pleased to see more people are converting these Polos 

My motor mount is now done. We used also the original mounting piece (arm).
I asked local plumber's shop for a ring used for tightening heavy pipes and they had one that fits perfectly around the Kostov 9'. Then some welding had to be done and the result is sturdy. I will post a pic when I will take one, explains much better.

Now we are working on battery boxes. I'd like to know how many kilos your batteries weight in the back. Are those TS 40ah's? Is the car still a 5-seater? Our back battery box will hold 30 TS 90ah batteries ~ 100kilos incl. battery box. Maybe even more becouse there is not much room in the front. 90ah cell is too tall to fit on the motor, it hits the bonnet. 9 cells will fit where the radiator used to be.. There are 10 cells to mount.. somewhere.. 

Yes, I'm very interested.
-Tomi


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## jhuebner (Apr 30, 2010)

Tomppa said:


> Hello jhuebner and thank you for your reply!
> 
> I'm pleased to see more people are converting these Polos
> 
> ...


Yeah I can imagine it quite well.



Tomppa said:


> Now we are working on battery boxes. I'd like to know how many kilos your batteries weight in the back. Are those TS 40ah's? Is the car still a 5-seater? Our back battery box will hold 30 TS 90ah batteries ~ 100kilos incl. battery box. Maybe even more becouse there is not much room in the front. 90ah cell is too tall to fit on the motor, it hits the bonnet. 9 cells will fit where the radiator used to be.. There are 10 cells to mount.. somewhere..
> 
> Yes, I'm very interested.
> -Tomi


Theres 99 LFP40 in the back, thats about 150kg. I haven't registered the car yet, so I don't know if it will become a 4-seater. But I wouldn't mind.
An issue with not putting batteries in the front is weight distribution. At 150kg the car is quite low at the back. Without batteries in the front it rides really high. Results in a weird look and little grip. Maybe you can mount some batteries horizontally?
I mounted 48 cells up front, so about 70 kg.


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## Tomppa (Jun 30, 2012)

It's been long time since last post... 

I suspended the project because personal matters. Then it got forgotten and 
it has just been laying in my parents yard for the past years. 

But oh my god. It moves, it's alive.
I'm speechless and shocked. It's so quiet.

I used two 12v 60ah lead acid starter batteries in series and limited battery amps only to 100. With 24v and 100a (2nd gear, ~3,3hp) top speed was around 15kmh!  I just love how lightweight this is.

I and my brother drove a few times around parents terraced house and to the end of the street before Soliton sensed batteries are depleted and decided to protect them. It was really easy to get the Sol Jr to work.

I have made the boxes for the lithiums. First plan was to install them in to the trunk but now I'm thinking it's then too heavy in the rear. It looked like it was just going to pop a wheelie.  So I guess I ditch the old boxes.  Better plan is to install 40 where the back seat is and 9 to the front space where the radiator was..

P.s Just random thought. This is just guesstimate! ~12kwh usable energy. 15km per hour and 2,4kw power from the batteries. 12kwh/2,4kw = 5h. 15km/h*5h = range 75km. I just wanted to do some math!


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## Tomppa (Jun 30, 2012)

Small update.

Today I installed 30 cells to the old battery box. Voltage was just bit over 100v. I am going to drive it on public roads (needs transfer permit + insurance) to get the new battery box made and installed. It's only ~4km trip back and forth. Still don't have welding equipment or skills.

I reprogrammed Soliton's parameters to following:

*Min bat voltage under no load *84v*
*Min bat voltage under load *78v*
*Max bat amps *150a*
*Max motor current *300a*
*Max motor voltage *70v*

Max power was around 14kw. I don't have rpm sensor and limit enabled yet, and I didn't install bms yet. Also there was no liquid cooling for Jr. So I want to be on the safe side.

Acceleration was surprisingly good. It managed to reach ~50km/h fast(ish) with 2nd gear. Then, I guess, it ran out of motor volts. There is minor wheel spin when driving on gravel I tried shortly even on tarmac, but handbrake didn't hold.

I can't imagine this with full voltage. I think I'm going to keep motor amps limited only to 300 just to protect Polo's gearbox. Okay, maybe 400, or should I try 500 

P.s Sorry for the lack of videos and pics. I should post some.


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## Tomppa (Jun 30, 2012)

I got the transfer permit + insurance on thursday. It was just for a single day and it costed 28 euros (autotrailer would have been 46e per hour! )

But it was worth it ! I even passed one suv during the trip My ev-grin got wider














The shop that does the battery box didn't want to keep the batteries in the car or the shop so I took all the 30 cells back to our garage.

Of course now that I've driven with 30 cells they are at different SOC so I wanted to balance the whole pack. I have charger for a single cell (3.65v, 6amp) but soon it became clear that it would take ages to charge cells one by one. Although I started with it.. Got 3 cells topped.. 

I decided to put minibms modules on each cell and wire the whole pack in series to use my 1500w TcCharger. Friday evening well spent It was tedious job.




















Also I managed to touch one bus bar with another when tightening the bolts. BE REALLY CAREFUL WHEN INSTALLING THEM!!! Luckily only minor mark on the bus bar was the result. SERIOUSLY, BE CAUTIOUS!








Remember those 3 topped cells? Rest voltage is around 3.4v on them, others are at 3.30-3.34. It took maybe 10 secs before they started shunting and I had to terminate charging. I used chargers enable and +12v for ON/OFF command. If I recall correctly, minibms shunts max 1 amp. Charger puts out 8 amps. Now I need cheap and easy way to "bleed" those cells back down. Using minibms to get the pack balanced is too slow also..

Here is some of my thoughts for the high voltage safety and human pain threshold. Obviously you want to avoid all short circuits, even low voltage ones. Good advice is to wrap your tools with electric tape. This reduces risk of shorting things. For higher voltages it also helps by isolating your hand from pack voltage. I've had my first shocks. I wanted to test different voltages on myself I increased voltage by adding one cell at a time in series and so on.. For my experience at 50volts you can feel it on your finger, yes, I experienced only with finger on one hand. Where as 70 volts starts to be uncomfortable. Here is good advice also, keep your other hand behind your back or inside your pocket when working with your pack! When I was installing bus bars I used some CRC for some bolts being tighter. Voltage in series were maybe 40 volts but my hand had CRC on it. I somehow managed to zap myself hand to hand. Didn't hurt but I wasn't expecting it so I got bit scared. All in all, if your skin is dirty or you have cut etc., your skin resistance goes down and you could experience shock with even lower voltages. Like I did... Skin resistance varies greatly with different people and point of contacts, so I would not set any safe limit for voltages.

That's all for now. I hope someone finds this rather long post informative. Wish I get Polo back as soon as possible.

Regards, Tomi


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## Tomppa (Jun 30, 2012)

I made some purchases from ebay and those took ages to arrive. Finally I have wired all the high voltage wiring inside the engine compartment.














I bought Fotek SSR's to control the heater and the DC-DC. Up^ is a pic of the inside of the junction box. Those SSR's are cheap (~3 euros a piece) chinese fake ones, but they seem to work pretty well with the lower current draw. I didn't want to use the kilovac relays for so small currents. I ran the heater for over an hour but the SSR didn't have any issues with overheating or anything, which was quite a surprise for me. They barely even warmed.

I use mc4 holder and inline fuse rated for 15a for the accessories. Also I've made a smaller electric box for DC-DC. Inside the box is 5a fuse (250v) and 7a 100uH inductor to protect the device from ripple. Mc4 wires and connectors are usually used with solar power devices but they offer ip67 protection and are rated up to 1000v. So they are excellent for my application.

I also made some current measurements Link to youtube video Here is another video of measuring the heating "capability", which is quite low sadly. Turn on the subtitles if you wish to know what I say

Inside the heater core there is one 1500w element. I ripped it out from a broken heater. It was originally used with 230 volts which is the standard AC voltage here in Finland. Let's do the math:

1500w / 230v = 6,8a
230v / 6,8a = 33ohms

I actually measured the resistance of the element. When it is cold it's over 100ohms iirc. As it heats up it dropped all the way down to 27ohms and after applying more power to it, the resistance started to climb again.

So in my conversion the maths goes:
150v / 33ohms = 4,5a
4,5a * 150v = 675w

The heating output is 600-800watts. I measured 4,7 amps going to the element. It is low but I think it is enough to defog the windshield, which is a requirement for the inspection.

For serious heat I think one should use atleast 2kw of power..


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## mora (Nov 11, 2009)

Good going. For serious heat you need at least 6kW of heating power to keep your windows clear if it is really cold (-30C) outside. 2kW will do nicely at around zero degrees celcius.

I've also accidentally made busbars touch each other when disassembling a battery pack. Instantly molten copper everywhere. Luckily not in my eyes


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## Tomppa (Jun 30, 2012)

Hey mora, I have now installed the Ev display (from Cleanpowerauto). I can now see how much the heater element draws current and what power it has. It is, like I thought, 600-800w (~5a) depending on the pack voltage. The element is 230v.. If I can't pass the inspection with it, I'll change it to 120v.

So what I've done. Battery box is done. On left, there is a small box, which contains 300a fuse, main contactor and Ev display sender unit.








Polo had a huge rust problem. Drivers foot well was in bad condition. It has now been repaired. Pic is from the under of the car. You could see the carpet. Also it got new tires.














I visited the inspection office and asked about the electric "modification inspection". I need to follow E100-rules. Friendly inspector send those to my email in finnish. For example, there has to be some kind of a way to inform the driver that car is driveable. I had a good idea to remove instrument cluster and put a green led to show the driver that the car is running. (Soliton has "run output")













..It was horrible idea. Firstly, the cluster was pain in the a$$ to get off. Especially the speedometer cable was in very tight space and of course it was very hard to clip off. Secondly.. This is 30 yrs. old car. Disassembling and assembling the cluster parts was rather easy, but because there was some corrosion or gunk half of the led lights and the clock didn't want to work. But I made it!

When I drove the car back from rust repair, I wanted to try acceleration. And managed to film it too.
200 battery amps max, motor voltage is still 72 or 96v. 3rd gear. I think the low motor voltage is a limiting factor here. I hadn't power brakes wired, so it was bit scary.





P.s Level driving drew 40-50 amps at 50km/h so 100km per charge is pretty close  at least when I change rear ball bearings... huh, more things to do.


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## mora (Nov 11, 2009)

Looks really familiar  Guess -89 Polo isn't that much different from same year model Golf which I had. I had same rust problem in drivers footwell but it was way worse. It passed annual inspection many times even though carpet was clearly visible from the bottom


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## Tomppa (Jun 30, 2012)

Hi to all.

The car was succesfully (and finally) inspected in may. Here is the link to evalbum.

I also started using public charging station in my home town. It costs 1€ per month (for the time being), kinda free electricity I guess?
Polo, for being an older car, managed to get in to a local electricity supplier consumer magazine.  Article is in finnish, but maybe google translate can give you some hints of what is written.

Happy electric kilometers and miles to everyone!
-Tomi

Oh and btw. I used 200 amps battery limit (now it's 270a) on Soliton and managed to achieve 130kmh per hour so:

Highest consumption is:

140v x 200a / 130km/h = 215whrs per km 

Or 350whrs per mile.

Lightweight is the way to go ! 

I wired minibms so that it lights a light in dashboard when/if any cell drops below 2,6volts. I have never seen the light switched on, exept for testing purposes..

Thank you all for your replies and help !!


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## Pepy1923 (Dec 26, 2020)

Ace_bridger said:


> Watching with interest while I complete my Golf build.
> 
> Will keep an eye on posts and offer adivce where appropriate.
> 
> ...


Hello Adam . i want to convert a Passat 32B , its basic same car like yours. i live in Sweden . can you help me ?


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