No pistons, no fuel, no worries! Toyota Sera EV Conversion begins…

[TERRA Operative]

The thing ring gear won't prevent the cast flywheel from breaking apart. The torque loading is at the flywheel, input shaft/crank interface, so that's where the cracks (if any) will start.
A thin ring of steel won't stop that.....
I highly doubt it will be a problem anyway.

[cambelt]

Yes i would never have thought a ring gear could keep a cast structure together.
I was told this by a very old engineer a few years ago and even he said it would be unlikely if driven at normal RPM but if exceeded a good posibilty.
Dave

[VA61DETT]

Thursday, 7 May 2009

Been busy working on the battery box, this is a fairly complicated design with several steps to fit the 3 rows of cells neatly in the rear seat area, while avoiding cutting into chassis rails.

Planning the cuts & bends


Base and sides bent up


From another angle, few holes to fix.


We had to remove part of the centre tunnel, as it was a little tall.

Holes


The battery box will also include 2 fans which will vent out the bottom of the seat wells.
Still need to find a couple of nice large low profile 12v fans, some small thermo fans or server fans should do the trick.

More pic's of test fitting to come!

-A

[TERRA Operative]

Some nice 120mm Panaflo etc. fans will do the trick, and be quiet too. Get ball bearing versions for long term reliability.

[Mr Ed]

Wow! Awesome project!

subscribed

[VA61DETT]

Dash is out, Battery box is in!

No dash:


Hello Batteries!



Box test fit rear:


Side view


The box is a little far forward at the moment, still need to do a little manipulation of the floor pan & edges of the box.

Have sent modified accessory pulley off to engineering shop for keyway cutting, hopefully will be ready for the weekend & can move on to mounting the accessories and additional engine mounts.

-A

[greywolf]

My vote is go for some 24V fans. It will take very little wiring to get them to work, can get significantly more airflow for the same size, and to make sure you mount them in a way that is easily accessible. Don't make life hard by having to remove all the batteries to have to replace one.

[ra23celica]

Kudos to you Aaron,
This is an excellent project. Well done.
Are you going to upgrade it to inductive re-charging, so it re-charges faster?
And I take it that with your LION cells you have got the system for charge equalisation to extend the life of the cells as much as possible?
Cheers,
Mitch.

[OnAll-FOUR]

Kudos to you Aaron,
This is an excellent project. Well done.
Are you going to upgrade it to inductive re-charging, so it re-charges faster?
And I take it that with your LION cells you have got the system for charge equalisation to extend the life of the cells as much as possible?
Cheers,
Mitch.

Upgrade to Inductive recharging? what do you mean by this?

[TERRA Operative]

Regenerative braking is the correct term.

[VA61DETT]

Umm not sure about the inductive charging bizzo.. Big coil in drive way / car??
Each cell has a balancer circuit which talks to a central battery management system, so hopefully the cells should be good for quite a few years.

-A

[ra23celica]

What I am talking about is the recharging system used by the EV-1. It is able to dump much more current into the into the car more quickly because the charging station is hard wired to your house. It works like a transformer but in two part - a charging station on the house and the second part in the car. You slot the inductive 'paddle' into the car, it forms a complete transformer and power is dumped in. I don't believe that this known as regenerative braking, but feel free to correct me if I am wrong.

And now maybe a little off topic:
Go the Top Gear electric Kingswood - still lapping Oran Park!

[MWP]

The inductive charge paddle used on the EV1 has nothing to do with "fast charging".
Its just a way of making a connection without electrical contacts.
The paddles are water, moisture, dust, etc proof which is why they are used.
An actual cable can move more current if required with less transmission loss.

Anyway, you can also only charge the batteries up to a certain rate... anything over that and they overheat and get damaged. Li-ion also have been known to explode from overcharging or charging too quickly.

[ra23celica]

Thanks MWP,
I had that wrong. I blame the movie "Who killed the electric car". Now I'm heading to the library to borrow some electrical eng. books a learn this stuff properly.

[OnAll-FOUR]

What I am talking about is the recharging system used by the EV-1. It is able to dump much more current into the into the car more quickly because the charging station is hard wired to your house. It works like a transformer but in two part - a charging station on the house and the second part in the car. You slot the inductive 'paddle' into the car, it forms a complete transformer and power is dumped in. I don't believe that this known as regenerative braking, but feel free to correct me if I am wrong.

And now maybe a little off topic:
Go the Top Gear electric Kingswood - still lapping Oran Park!

As it has been stated, this is a very inefficient way of doing it hence why I queried it.

I think it might have been referenced in that thing about who killed the electric car because it was a design flaw not a feature People have also talked about the idea of having it int he garage slab so that when you drive home it will automatically start charging our car for you and you do not need to "plug" anything in. nice idea but again very wastefull.