Charger Arrives

I received the charger. It's an Elcon 2KW charger with profile for 45 off Sky Energy cells.

The vacuum pump also arrived along with fuses, contactors, cable etc.

Tomorrow I am getting a steel fabricator in to measure up for battery boxes and motor mount.

I just got confirmation form the certification engineer that I don't need to use a big red switch. The new version of NCOP14 allows for isolation of the battery via 2 contactors operated from the ignition switch.

Parts have also arrived for my battery management system. It is a processor based system using a PIC chip for each cell, mounted externally from the cells, 16 per board. The master does coulomb counting and shows SOC for the pack and remaining distance to travel.

Batteries

The batteries arrived just before Christmas. 45 off Sky Energy 100AH cells. I spent a few hours bolting them into groups of 5 using the mounting plates provided.

Its pretty scary wielding pieces of uninsulated metal around the terminals of these cells as they can put out over 1000 amps each.

I have now finished my open source DC controller and it is all set to be tested at high voltage.

I am waiting on fuses and contactors before wiring up the whole battery pack.

For a BMS I am going to use another open source project from http://www.batteryvehiclesociety.org.uk/forums/viewtopic.php?t=1245

Motor Installation

After 3 long months of waiting the gearbox, couplers and adaptor plates arrived. At first try the coupler did not fit so back to Geoff for some fine tuning. When it came back everything fit ok so I fitted the adaptor plate to the motor then the coupler and after a lot of time sorting out the right bolts and lining up the motor on the hoist I fit the motor to the gearbox and tightened all of the bolts.

Next I lifted the motor gearbox into the car and bolted it to the front and rear transmission mounts. I the refitted the drive shafts to the transaxle and remounted the wheel hubs and steering arms. I then connected the output of the oil pump to the input to bypass the oil cooler in the radiator, as it will no longer be needed. The majority of the heat generated in an auto transmission is from the torque converter and this is now gone. I filled the transmission with atf and I was ready for a test run.

I put the transmission in D and connected the motor to the old starter battery and hey presto the wheels started turning. There was a very short delay between when the motor started turning to when the wheels turned, maybe 1/4 second. I don't know what this will feel like when driving yet but I have some ideas on fixing the problem.

I installed the ceramic heater core in the heater unit and put the dash back in. About another 4 hours work all up. I am still waiting on the coupler and adaptor plate for the motor / gearbox. This was bad timing as I gave it to Geoff to convert just before he went on leave. I should get it back next week if all goes well.

I have been working flat out on a design for the motor controller over the last few weeks. It's an open source design and I am just doing a bit of fine tuning and the final board layouts. Beta testing of the unit is almost complete with no major issues. http://ecomodder.com/forum/showthread.php/paul-sabrinas-cheap-144v-motor-controller-6404-224.html

Its a long read at 224 pages and growing. Paul has done a fantastic job with the design. We are arranging a bulk buy of parts for Aussies, see http://www.aeva.asn.au/forums/forum_posts.asp?TID=1160&PN=1

Dashboard gone
Dashboard removed

Removed heater core

Being a glutton for punishment, I decided that the next thing to do would be to replace the heater core with an electric element, as there will be a severe lack of hot water in the car after the conversion. I sourced a 120 VAC ceramic heating element from a guy in the USA who sells them to EVers in Australia.

The removal of the dashboard took about 4 hours and is possibly the worst part of the whole job. Without the manual I think it would have taken 8 hours. The most dangerous part of the operation was removing the air bag. Apparently they can go off with very little provocation, hmmm very similar to a woman. Next is removal of the steering wheel using a steering wheel puller, $20 from Supercheap Auto. The instrument panel was removed and I noticed that the front panel was cracked. It looks like a trip to the wreckers for a replacement.

While I was disconnecting some of the wiring connectors I noticed a non standard unit wired into the ignition wiring. It turns out it was an aftermarket engine immobiliser and remote keyless entry. The wiring was very poorly done with wires cut and twisted, no connectors and no solder. As I didn't get the remote control when I bought the car I removed the unit and restored the wiring to original. Finally after removing the dash & the aircon unit I got to remove the heater unit. The heater core will have to be modified to allow the mounting of the electric element into the old core frame.

I sold the old engine on Ebay this week. I listed it last week and it sold for $1.50. It turned out the guy who bought it didn't check where the engine was. He was in Adelaide and I am in Brisbane - go figure. Anyway he defaulted, I relisted and sold it for $100 to a local. He also took a lot of the other bits I didn't need, so I won't have to dump them.

The plans have evolved a bit more now. The automatic transmission is now on it's way to Sydney so that Geoff from GT Tooling can make the adaptor plate and coupler. The plan is to remove the torque converter cut it open and use the internal splines to create a coupler. The secret is to recreate the normal transmission fluid path from the centre of the pump shaft back to the outer shaft where it returns to the transmission. He is also going to make a plate for the rear of the motor to mount the air conditioning compressor and power steering pump

The other problem to overcome is that the transmission clutch for 1st gear will not engage if the transmission pump is not operating ie when the car is stopped at lights etc. I am going to do some tests when I get the transmission back to see how long the pressure remains in the box after the motor stops turning. This should be proportional to how good the seals are. Geoff has suggested that an accumulator connected by a solenoid valve could be used to apply pressure instantaneously to the box when the accelarator is pressed. The logic behind this may be a bit hard to apply and it may be restricted by how fast the clutch can operate compared to the motor.

The other option is to use an electric pump operated from a pressure sensor to keep the pressure up to the clutches. The pump would only operate when the pressure drops below the point at which the clutch would disengage. To make this more efficient, the pump could also be turned off if the brakes are applied, so that when you lift your foot off the brake the pump starts and by the time you apply the throttle the clutch has engaged (if it engages fast enough). Either way there is a bit of testing to do before I proceed any further.

I have settled on a controller for the project. I will be building the controller myself from an open source design see link http://www.paulandsabrinasevstuff.com/evmotorcontrollers.html
It is a 144volt 500Amp controller and it meets my requirements for power. Parts have been ordered andshould be delivered within 8 weeks. Construction should take a few more weeks after that.

For batteries I will be using Lithium Iron Phosphate batteries from Thundersky. I am still tossing up between the 90 Ah and the 160 Ah batteries. I was going to try to fit all of the batteries under the rear seat where the fuel tank was but the available space is just too tight to fit all of the 90's in the one spot. Depending on which battery I can afford at the time I will mount some under the rear seat and some in the engine compartment. I calculate that I can probably get about 90 Km range from the 90 Ah batteries and about 160 Km from the bigger batteries.

I am looking at 2 different battery management systems. The 1st is an open source processor controlled shunt device which has over & under voltage protection. The 2nd option is an active powered system where a small power transformer feeds each cell independently and the amount of current to each cell is controlled by the state of charge of the cell. This gives the best balancing but is limited by the size of 45 transformers and the addition wiring to each cell. The main advantage with this system is the simplicity. I will have to get a few batteries and do some testing to see which way works best and is safest.

ICE Removal

Transaxle ready for a cleanup

Anyone want a 1300cc Mazda ICE

Empty engine bay

Out with the ICE

The electric motor (Impulse 9) was delivered last week.

On Saturday I pulled the axles from the transaxle. This was hard going as the axle nuts wouldn't budge even after soaking in rust remover and using a 600mm break bar. In the end I removed the wheel hubs with the axles attached. The manual said to pry the axles out using a pry bar but I found using 2 bars one on either side more effective. I then loosened all of the engine mount nuts and made sure the engine was free of everything holding it in.

Today I removed the engine. I hired an engine crane and it popped out with no problems at all. I had to disconnect the air conditioner condenser because the return pipe was in the way.

I then removed the transaxle from the engine.