Step Seventeen - Creating the Charging System

Now that the car works, it's time to create the charging system.

I have all the chargers I need now. I have twelve 3.5 amp Australian made Calibre chargers and will be charging each battery individually through the 28 pin plug installed where the fuel filler used to be.

I've chosen this method because it's very cheap ($2000 cheaper than a single pack charger), and it allows every battery to be charged and balanced individually, without the need for an expensive battery management system. It's a win-win for simplicity!

As you can see, the chargers are low amp rating so a full charge will take some time. I would have loved to have bought twelve 10 Amp chargers but this is a conversion on a budget! Perhaps later on I can install more powerful chargers. This will do for now!

The first thing I had to get my head around was "Why don't the chargers all short out if they're connected on one circuit together?". This was answered for me by the crowd at www.evconvert.com where Dr. Larry Tilman has used the exact same charging system with brilliant results.

After a bench test with two chargers across a open 24 volt circuit (two car batteries) I discovered that the + and - of charger A are not interested in the + and - of charger B which is brilliant! The idea works!

I ended up buying out the entire new stock of chargers from the local SuperCheap Auto store. I then created a box big enough to hold 13 chargers (12 for the car, one for the headlights etc). Everything went fine until it came time to connect everything up. At that point I found that one of my new chargers had a fault that stopped it from delivering more than 1.4 amps, but most importantly my multi-pin plug has an interesting personality... Sometimes all 13 batteries are charging, and sometimes a couple here and there aren't. It all depends on how you hold the plug in! It means after I've finished charging I have to go round with a voltmeter and then manually charge any that missed out! Talk about frustrating!

Eventually payday came around and I was able to purchase a new 32-pin plug and socket setup from Lapp Kabel connectors. All up it cost $250 for the inserts, housings and panel mounted receptacle. Let's hope it works at that price. They better be amazing as I blew my whole fortnight's budget just on the charging plug! It doesn't help that Christmas is coming up as well. That's always a drain on the wallet. I wonder if my wife will mind if I'm her Christmas present this year? Hehehe...

HCB Technologies (my battery supplier) have been marvellous regarding that battery with one dead cell. I mentioned the faulty battery on Monday morning and they had a fresh one in transit to me no questions asked before lunch time. Can't ask for more than that! Thanks HCB Technologies, you guys rock! :) The new battery slotted right into place and is happily charging with the others as I type this. The other glitches were the high pedal lockout not working, and the sticking contactor. The sticking contactor had a simple solution - change the main cables around the other way! The contactor has a + on one side, so I swapped the "battery" and the "controller" cables around and tadaa, all sorted. I couldn't get the contactor to stick no matter what I tried. Awesome stuff! Another glitch fixed!

While waiting for my new recharging plug and socket to arrive, I had a visit from fellow converter Nick Smith from Auckland (you can check out the beginnings of his EV right here).

Thanks to a circuit diagram he whipped up we were able to wire up the high pedal lockout using a simple relay and the switch on the base of the pot-box. A couple of hours later we'd sorted out the high pedal lockout problem. To "start" the car now, you turn the key just as you would a gas engine. The key is turned all the way to "start", then you let go and it stays at the "ignition" position like any other car. Once the contactor has "clicked" once it will stay closed via the relay. The really cool part is that none of the above will happen if your foot is pressing on the gas pedal! I'll create a circuit diagram soon I've had more caffeine and can concentrate better on this glaring monitor in front of me. The most important thing is that the three glitches are all sorted.

Nick and I began work on my last safety switch too. I'm installing a switch which breaks the contactor connection when you open the gas cap. It's really simple stuff as I'm using the safety cutoff switch from the bottom of the heater - remember seeing it on video 11? It's currently mounted in front of where the gas filler cap closes, and I'll wire it up this week. Pretty simple stuff.

I want to wire that gas-cap cut-off switch before my charging plug gets here and then I'll finish up the charging box, rewire a few things and hey presto! All done!

After a bit of thinking, there are still a handful of things I need to sort out before I can transport the car to Auckland for certification. I compiled a list (photo 8 below) so I could make my way through them and get that darn car on the road at last! As you can see, there's still about $500 worth of stuff in that list, and then another $815 required for the car transporter ($265) and final certification ($550).

A little bit of good news. My mum's partner is a mechanic up in Auckland and he's offered to replace the CV boot for free when the car gets transported there! That's $130 I can scratch off that list. I was thinking of tracking down some second hand tyres with good tread still on them instead of new ones. Apparently, older, harder tyres are much better for EV mileage than fresh soft rubber ones. I could probably find some second hand ones for $40 each if I'm lucky.

My recharging plug and socket have been delayed again unfortunately. They were supposed to arrive Friday 7th Dec but after two cock-ups from the warehouse in Germany, the NZ branch has received the wrong part twice. It's now expected to arrive this Wednesday but with all the Christmas chaos I probably won't have the time to fit it until after Christmas. Quite annoying really. I find the only times I experience project delays is when I wait on tradesmen and suppliers to show up with the goods! The project would have been finished 2 months ago if everyone was on time. Oh well, I guess I'm just getting a little anxious to finish the EV and get it on the road!

Some good news however regarding the painting. I tried my luck once more with the can method. Now I know you're all groaning after the last attempt but I was pretty sure I knew what I did wrong!

Professional painting was going to cost about $400 according to the quotes I got, so I thought I might try it just one more time. This time I followed the instructions to the letter and bought a quality clear coat, instead of the $3.99 budget brand spray can.

I sprayed exactly as the can suggested and waited exactly as long as it told me to between coats. I even used a stopwatch! After wet-sanding the primer coat with a 1500 grit sandpaper, I waited a few days for it to dry properly. It probably didn't need it as it's summer here now and very warm. Then came the colour coat. And another. After that came the clear coat... aaaaand another, and one more.

5 anxious days later it was time to wet-sand the clear coat and then buff it up. This was a tense moment as I didn't have much hope from the last attempt. I sanded carefully with water everywhere, then let it dry. It looked awful at this stage. Out came the bottle of cut & polish and I got rubbing. A minute later it was dry and ready to be buffed off. It looked ok so far so I tried more. Very good. A little more? Wow, this looks impressive!

Long story short, it actually came up quite well! Not perfect, but not bad at all as you can see by the picture!

I've also been busy rewiring my voltmeter setup and replacing the little power isolator for my ammeter. Unfortunately I ordered a 5 volt voltmeter and when I plugged it in it died in the blink of an eye and the smell of a burnt microchip. I'm really glad they're only $8 each. So I'm off to order another one, although I think this time I'll order two. I don't have a lot of luck with them. The good news is that my voltmeter wiring is complete and works well, the bad news is that both my voltmeters are now in silicon heaven.

Thanks to the many donations from a lot of marvellous strangers, there's now enough in the kitty to get two new tyres for the front! I'm going to try and take the front wheels down to a tyre shop on Tuesday and get a couple of new ones fitted.

You can all see my favourite Christmas present too at the bottom of the page: Personalised Number Plates! Yup, I have the number plates "KIWI EV" awaiting pressing and then installation onto the car! Will that look cool or what! Talk about a stellar gift! You can thank Rob for that idea. He heard me thinking aloud about the KiwiEV number plate and asked, "Have you checked if it's available?" I told him I haven't because there's no way I'd ever be able to afford them anyway and the conversation moved on. He later told me he reserved them that afternoon. That was in November too. The sneaky bugger. Thanks Rob! What a great gift!

Not only that but Barry Lee from Grumpy's Sign Shop (Cambridge, NZ) donated some really cool decals for the Tredia. They arrived a few days ago and I applied them to the boot-lid right away! They look great thanks Barry! Check out the photo at the bottom of the page!

So my to-do list is getting ticked off quickly at this rate. There's not a lot left to do now.

My recharging socket arrived over the Christmas break and finally I found a spare day to install it (you know what Christmas time is like).

The install went very well. The plug is from "Lapp Kabel" connectors and it's a dream to terminate. Each wire hole uses a simple screw-down (like a chocolate block connector) but slightly more fancy. This version doesn't screw down directly onto the wires. Very impressive design. It should be for $250. Hehehe

It ended up taking about 8 hours to connect the new plug, socket and charging box, mainly because I triple-checked every connection and also installed separate 5A fuses at the positive terminals of each battery, just in case anything goes haywire with the charging system. The chargers also have 5A fuses built into the leads so there's not much chance of damaging them. Well, let's hope. :)

The new socket also has a metal flap on the top with a rubber surround so I don't have to worry about it fizzling away each time I wash the car.

Once the 12 new fuses were in, the plug installed and the socket wired up, I had to check the polarity of each wire with my little multi-meter and solder them to their respective charger. Once I was confident they were all connected up correctly (I checked three times) I started plugging each charger into the wall. I was a bit nervous but everything seemed to go like clockwork. A minute later I had all 13 chargers (one of those is for the accessories battery) connected up and charging the car! Woohoo!!!

After that little test run I unplugged them all and tidied up the wiring in the back of the recharging box. I did a few checks on everything but found no faults (yet) so it's all going perfectly. Very good!

A big thanks to Peter from the Czech Republic for giving me the link to that plug & socket - it sure beats my home made version!

After that, all that was left to do was to create a splash-guard for the motor (an old real estate sign) and then install the ducting for the rear batteries. Together those tasks took about 5 hours with coffee breaks in between.

I've also booked the car transporter to Auckland for the certification on the 4th of February. Let's hope it passes OK first time although I'm concerned the shock absorbers are getting old. I can't feel any excessive body roll but that's just me. Perhaps the pros will think differently. I hope they don't - new shocks cost a lot of money.

So after all that effort, please enjoy the video of the charging system saga, including a cheesy 18 second clip at the end of the video showing just how easy it is to recharge the car!