Prius plug-in displays battery of good points

Woah 26 Hp ....

Does this mean there is a lot off power "hidden" in our Prius ??

Because normally capacity as nothing to do with power in term of batteries

Unless they are upping the voltage when adding the Plug-in kit...

 

I believe bigger electric motors are on-board the plug-in Prius to push the extra 220lbs (due the extra traction battery) and so make the plug-in Prius capable of maintaining 62mph w/o ICE (current version can only do 42mph before ICE kicks in). Software is changed also, of course.

 

http://www.treehugger.com/files/2007/07/toyota_unveils.php

 

We know the peak output of the gas engine and the peak output of the electric motor do not meet. Therefore, we can not add 76 HP gas engine and 67 HP MG2 power to get the HSD peak 110 HP output. The reason is that the Power Split Device was design to split some power and create electricity to supplement the HV battery pack to the MG2.

I believe a simple change in PSD sun/planet/ring gear ratio would enable the Plug-in Prius to reach 136 HP peak power. Let me explain in detail. MG2 outputs 60 HP at 6,000 RPM (note: attached graph is in kW, not HP) while the gas engine outputs 76 HP at 5,000 RPM. In that moment, the PSD in the current 04+ Prius was configured to turn the MG1 (generator) to turn at 2,300 RPM -- spliting away power from the gas engine. If the PSD can be configured to rotate at 0 RPM, all the power from the gas engine can go to the wheels. Meanwhile, all the 60 HP of the MG2 can come from the larger Plug-in pack -- making the combined output of 136 HP.

There is a connection because if you double the cells to double the capacity, you also double the power output.

 

I have to say that the plug-in hybrid is very exciting indeed. Seems like they are off to a decent start albeit with much work yet to be done. I would have to say that in order to really gain the interest of both old and new hybrid buyers, Toyota really needs to show somewhere between 30 and 50 miles (on all electric) between charges...minimum. This will capture nearly all the urban and suburban comuters. 7 miles will not excite too many folks I fear; dont' think too many folks will be successful pluging in their cars at work. Many technical challeges lay ahead to achieve such a feet however it can be done; hopefully at a price most folks will "want" to afford.

 

Since the plug-in Prius has twice battery, the battery power becomes twice.
TOYOTA: News Releases
"*Based on TMC calculations; output that the system can achieve using engine power and electric motor power (electric motor power is dependent on battery power) "

Ken@Japan

 

First thanks a lot for your explanation about the PSD and the power in consumes. I easily understand now how you could gain power that way.

But I don't agree with your comment that I've quoted. Of course when you double the batteries you "can" double the power but only if you connect those batteries in series to double the voltage. Otherwise, if you wire them in parallel you get twice the capacity but no gain in power ?! So it all depends on how it was wired. I'm pretty sure it's in series since duration in a PHEV is the key vs power output.

Yeah sure but like I've said depending on how they are wired. I thought they were wired in parallel to gain capacity (aka duration) and not in series to gain power ?

 

The Prius battery is limited to just over 100 amps or 25 kwatts (about 34 hp) to avoid shortening battery life. Your electric motor is capable of 65 hp so doubling the CURRENT capacity by putting two battery packs in PARALLEL can give you extra peak hp (about 30).

JeffD

 

Article looks very good. I think a 20 mile electric only range would be a good compromise.

 

Stock Prius HV pack is 201.6 Volt with 6.5 AH. To get 22.5 kW output, you need to draw at 17C.

The Plugin HV pack have 201.6 V @13AH. It will only take the same 17C to draw 45kW.

 

Ooooh now I see... I didn't knew the current battery CURRENT was limiting the motor power. Of course, parallel wiring you can double the Amp and gain power IF the motor, converter, wires are built to support it.

(as you can see I'm not that good with electricity, but I try)

Now does that mean any increase in available torque ? ... 590 lb-ft of torque

 

2008 Prius curb weight is 2,932 lbs. When I got my 2006, it was listed as 2,890 lbs. Does Japanese Prius weight less?

220 pounds extra is not accurate. The extra pack should weight only 99lbs more.

 

power = ampere X volt
In parallel, power becomes twice on twice ampere value.
Of couse, it is true on twice volt value in series too.

Ken@Japan

PS. I was little late...after you realize that.

 

I wonder how much you would pay for plug-in capability. For me, the limit for where it makes financial sense seems to be around 4000$, considering that I pay 2$ per liter (7.5 $/gallon). The only price on 3-rd party plugin mods that I have seen was from 24000$ upwards (hybrid-plus). Edrive systems mentioned a price around 10-12.000$, but that was in 2006, when the product was not quite ready, no news on their site since. Any opinions on whether a plug-in upgrade for the Prius will ever become an attractive proposition for the average Prius owner ?

 

Hi Syco, et al,

The MG2 inverter was probably sized for the MG2 motor capacity. That is what I would do. Then there would never be a question of MG2 inverter handling the draw MG2 would make.

In normal Prius operation there is extra power from the Engine/MG1 circuit, which combines with the battery power. So, MG2 inverter is much bigger than the battery power already.

 

For me, the calculation is not an economic one: I am not concerned about the price of gas. I want to be able to drive ELECTRIC. The after-market plug-in conversions for the 2004-2008 Prius (CalCars, EDrive, etc.) does not allow the Prius to be used in all-electric mode except at slow speed and very light acceleration, just as the presently-available after-market EV switch. The conversions allow about half your energy to come from the grid for the first 60 miles or so. But the gas engine will run, providing the other half.

As it presently exists, the Prius lacks sufficient electric-motor capacity to meet my desires for a plug-in.

But if Toyota re-designed the Prius as a plug-in hybrid, capable of driving at freeway speed for 30 miles without ever starting the gas engine, and only starting the engine after that distance, I would pay considerably more than a purely economic analysis would justify, simply because I want to drive electric. I think I'd pay $50,000 for such a car. Give me 100 miles at freeway speed before the gas engine starts, and I'd gladly pay $60,000 and perhaps more.

 

The 68HP of the Prius's electric motor should suffice for producing speeds up to 60-70 mph. The reason it's so slow in EV mode is the battery. While the motor can accept 500 V, the battery can only produce 200 and the remaining has to come from the ICE+MG1. I'm not sure if it' quite that simple, but if a battery could deliver 500V and the required Amps, you should be abe to have reasonable EV performance. This leads me to wonder if anyone here has experienced any of the battery-modded Prius'es. They probably don't quite get 68HP from the battery, but they should be able to perform better than the standard Prius does in EV mode.And I don't see why Toyota, provided batteries capable of supplying 68HP become affordable, shouldn't be able to give us an upgrade capable of feeding the motor the power that it can use without having to start the ICE. Unless someone can prove me wrong, I prefer to remain hopeful (although I admit it's a thin hope).

 

I think you nailed it on the head there. The existing inverter and batteries are under rated for the existing motor. A larger battery is capable of putting out more current at the same voltage, and assuming the inverter has been upgraded it can deliver more power to the electric motor.

Rob

 

You're right, its not that simple but you're on the right track. My grasp of it is only slightly better...

As you imply power out of the motor is limited by the power that can be delivered to the motor from the battery through the controller/inverter. The battery is only 200V, but the inverter includes a voltage converter that steps it up to 500V. This is needed to overcome the motors back EMF at higher rpms. The downside of this is it reduces the current delivered by the same factor. For that reason, the "boost" converter can be turned on or off as needed. More battery = more current as well as more capacity.

more capacity = more range, more current = more zoom

Rob