2008 Gen 2 Prius Plug-in Conversion

[evric]

This photo shows how the 2KW TC Charger charger is fitted - right out of the way.
See my blog for more detail on how the charger was fitted:
www.evplus.com.au/evplus_blog.htm
Note: Because of the orientation of the charger ie. the heatsink fins being horizontal, I have placed 3 off 240V fans on the charger mounting bracket (not visible in this photo).
The mat was purchased from the US, as this Toyota part (made for the Gen2 Prius) is not available in Australia.
The mat sits on top of the clear polycarbonate sheet, which is screwed to the battery frame.

[evric]

After installing and using the PIS system, I was upset to hear lots of beeping at times and thought that the PIS Front Controller had problems. Associated with the beeping was the notice flashing up on the screen "EV Mode not available at this time..." or similar. (PIS = Plug In Supply, California)

Before we go too much further, firstly let me tell you a bit about part of the wiring from the PIS Front Controller to the Prius.
There are two wires which connect from the Front Controller to the wiring of the Prius EV switch (see "EV Switch Wiring" menu item on the left.) The EV switch comes preinstalled in the Australian Gen 2 Prius.

After much listening to beeping and a lot of thinking and watching to see when the beeping occurred, the problem is, I think, a design / setup problem with Front Controllers sent to Australia (which are the same ones used in the US).

In the US Prius, the top EV mode speed is around 34mph (55kph) (or more I have read - someone please verify this for me, thanks).
The Australian Prius is set to turn off / not allow "EV Mode" above 45kph (around 28mph).

This causes a problem between 28mph and 34mph when the front controller tries to turn on the EV Mode. Of course in the Australian Prius that is not allowed and it keeps trying and beeping, trying and beeping, about every 6 seconds, complete with a warning notice on the centre screen.

The reason this is very annoying is that a popular maximum suburban road speed (off the main roads) is 50kph (31mph), right in the middle of this disallowed range. (The main roads are 60kph (37mph))

I asked Robb from PIS if he could supply a special Front Controller for us Aussies and possibly New Zealanders and possibly Europeans. I am willing to pay for it.

Robb is a great guy and easy to correspond with, but this time I didn't like his response...

"I can't change the software. No demand except from yourself to justify the expense."

...

"No. The software is based on Toyota software and I cant change it."

"The beeping is normal. It does not beep all the time. I don't know why."

I have worked out why and told him.
It is not the Toyota software that needs changing, it is the programming in the PIS Front Controller.

So, after you non-US residents install the PIS Front Controller and have the same result as I have above, please ask Robb to send you a special Front Controller... or better still ask him to supply you one specially programmed for your country, when ordering it. Specify maximum EV Mode speed = 45kph (28mph).

Please let me know how you go.

************************************************** *******

Update - 07/10/17
I have now completed a GPS project (using an Arduino) which has fixed this problem for me.

Full details will be added soon.

This part of my continuing blog on www.evplus.com.au

[evric]

My Gen 2 (2008) Prius, on the last fill up (which is not very often) after travelling 1000km, I put in 27.8 Litres, which easily calculates to 2.78 L/100km or just over 100mpg (imperial). Prior to filling the tank, the fuel gauge showed half full.

My wife drives the car most of the time, but when I drive locally, I always use the "ICE Kill Switch" and travel fully electric! ... and loving it.

Please see my recent post with news about Plug-in Supply Inc (Robb Protheroe).
http://ecomodder.com/forum/showthrea...tml#post562902

Eric

[broski499]

Fantastic job. Amazing how stock it all looks. How long does it take to charge it 100%. Are you able to gauge the percentage of the pack's charge state? I have a 2008 prius and have wanted to do this but the cost is a tough sell. has anyone tried rigging up a system that allows for grid charging of the stock battery so you always start at 100% charge state. I'm in California, wonder if a solar roof could trickle charge the stock battery while at work... I know small solar panels can't do much, just curious. Anyway, bravo for doing what I have always wanted to do and doing such a nice job.

[evric]

Originally Posted by broski499

Fantastic job. Amazing how stock it all looks....

Thanks for your comments.
The additional battery pack is 40Ah and the system uses around 26 - 28Ah then switches the Plug-in Supply kit off. Perfect for the LiFePO4 cells.
I use a JLD404 meter to monitor each day's usage (Ahs) and then reset it each morning ready for the new day. This lets me know how long I have to leave it on charge.
The charger pushes in just over 6 Amps and so the pack takes around 5 hrs to bring it back up to 100% (after using around 26Ah). Of course, this will vary each day. Charging every night on off-peak power. This charging arrangement only tops up the additional battery pack. I don't know of anyone trying to externally charge the original Prius battery pack. Probably not worth the trouble.
All the best
Eric

[S Keith]

Originally Posted by broski499

Fantastic job. Amazing how stock it all looks. How long does it take to charge it 100%. Are you able to gauge the percentage of the pack's charge state? I have a 2008 prius and have wanted to do this but the cost is a tough sell. has anyone tried rigging up a system that allows for grid charging of the stock battery so you always start at 100% charge state. I'm in California, wonder if a solar roof could trickle charge the stock battery while at work... I know small solar panels can't do much, just curious. Anyway, bravo for doing what I have always wanted to do and doing such a nice job.

Great way to cause cycle wear with no benefit. Usable capacity of the Prius NiMH pack is almost identical to the total capacity of the 12V, so conceptually, you're trying to gain some benefit by adding additional energy equivalent to the capacity of your 12V battery.

The good thing is that your battery will probably be very balanced most of the time.

The bad thing is that your battery will sustain accelerated cycle wear due to you forcing the battery to 100% SoC. This increases the depth of discharge and adds battery cycles where there otherwise wouldn't be any. This generally equates to reduced battery life.

Additionally, the repeated forced over-charge would likely cause accelerated capacity loss due to inducing voltage depression and would require you to periodically discharge the battery via an external means to recover lost capacity.

The mpg benefit would likely be very hard to measure given that you're adding very little stored energy.

Grid charging is very beneficial as a preventative maintenance tool, but this is typically done on a once per 90 days time frame.

Calcs:

HV battery:
6.5Ah * 201.6V = 1.31kWh
40% usable = 0.52kWh

12V battery:
45Ah * 12V = 0.54kWh

[evric]

[QUOTE=S Keith;562959]Great way to cause cycle wear with no benefit. Usable capacity of the Prius NiMH pack is almost identical to the total capacity of the 12V, so conceptually, you're trying to gain some benefit by adding additional energy equivalent to the capacity of your 12V battery.

The good thing is that your battery will probably be very balanced most of the time.

The bad thing is that your battery will sustain accelerated cycle wear due to you forcing the battery to 100% SoC. This increases the depth of discharge and adds battery cycles where there otherwise wouldn't be any. This generally equates to reduced battery life.
............

Hi S Keith,
You are replying to someone elses passing comment/reply on this thread.

What happens with the Plug-in Supply(PIS) system is that it actually reduces the number of cycles on the main pack. The PIS system keeps the main pack at around 62% SoC, which is the optimum for cell life (set by Toyota). This is just one of the many smarts of the PIS system (unfortunately - no longer available - see notice below).
Eric

[evric]

The economy figures for my last two petrol fillups in the PIS Plug-in Prius:
2.8L/100km 84MPG(US) 101MPG (IMP)
2.6L/100km 91MPG US) 109MPG (IMP)

Each one was after driving at total of around 1400Km over many days with charging each night

Keep in mind this is with my wife driving the car most of the time and doing lots of hill work and highway driving.

[evric]

Notice: Plug-In Supply in California are no longer supplying kits for making your Prius a plug-in!
Their website now has no mention of the kits, not even a notice to say what happened to them.
I contacted Robb and asked about it and he simply said:

"Hi Eric,

Yes I have shut down that business.

Regards
Robb"