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Discussion Starter #1
So I was thinking to make the most efficient use of the range extended, that it might be a good idea to have it cut off as soon as the batteries are fully charged. I'm not sure if this is already done or not. Would this constant charging and discharging during range extend mode result in deminished battery life? Will the range extended be able to charge the batteries fully while meeti g the demands of the vehicle? I'm hoping this has already been incorporated, but thought I'd make the suggestion just to be sure.
 

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They're designing the range-extender behaviour to maximize battery life. Everything I've seen shows the range extender starting and stopping to keep the batteries above 30% but there could be different modes of operation.
 

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Discussion Starter #3
manual control of range extender

or perhaps if there were a way to take over control of the range extended manually. If your like 5 miles from home and it's charged the batteries from 20-50% you might want to save the full and wait till you get home to fully charge.

I think it's a good idea to have the generator stop when the batteries are fully charged especially in city driving. While your stopped at a red light or stuck in traffic, it should be able to charge the batteries much more than driving down the highway. Once the batteries are fully charged, I'd like to go back to full electric mode. Just a thought.
 

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They're designing the range-extender behaviour to maximize battery life. Everything I've seen shows the range extender starting and stopping to keep the batteries above 30% but there could be different modes of operation.

I think this is pretty close. My understanding is that the engine turns on at 20% state of charge (SOC) and then turns off at 30% SOC.

At nominal highway speed (~65 mph) the battery is dissipating around 20kW and the ICE is generating ~53kW. The net effect is 33kW of charging. The 10% SOC is 1.6 kWh. So in just 3 minutes the ICE turns off, then in about 4 1/2 minutes it turns on again.

There seems to be a lot of obsession with not using any gasoline by tweaking the lower set point of the on/off controller especially when you are "almost" home. On the average, you'll be at the 25% state of charge when you get home (assuming you are already in hybrid mode). That is only 0.8 kWh of gas "wasted" this is worth four miles (5 miles per kWh) and at 50 mpg expected that's just 0.08 gallons; about 1 cup 4 1/2 tbs.

... you be the judge
 

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Very cool. Thanks nlh_90210. Thats just what I wanted to know. The less gas I use the better. I want to be able to tell all the OPEC countries to keep their oil! :D If this car were on the market already, id be headed to GM first thing tomorrow!
 

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Very cool. Thanks nlh_90210. Thats just what I wanted to know. The less gas I use the better. I want to be able to tell all the OPEC countries to keep their oil! :D If this car were on the market already, id be headed to GM first thing tomorrow!
You might use so little oil, that you can tell those pesky Canucks where to go too.
 

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Thanks FrankyB, perhaps I should have done some more research before making this post. Im glad that theyve already thought of this. However, id still like to see the option to have some manual control over the range extender. Im sure most will use the automated mode, but I think some of us might like to have more control over the range extender to optomize it for our specific driving conditions. Im not sure how this would affect the battery life. I would think that the range extender should come on at 20% regardless in manual or auto mode so the SOC doesnt damage the battery. So long as the battery is above 20%, I think itd be good to let the driver have a little more control if they so choose.
 

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I have a feeling you'll void the warranty on your battery if you let it drop below 30% to save gas. I'm sure there will be lots of people tinkering around with their volts that do that though.
 

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Thanks FrankyB, perhaps I should have done some more research before making this post. Im glad that theyve already thought of this. However, id still like to see the option to have some manual control over the range extender. Im sure most will use the automated mode, but I think some of us might like to have more control over the range extender to optomize it for our specific driving conditions. Im not sure how this would affect the battery life. I would think that the range extender should come on at 20% regardless in manual or auto mode so the SOC doesnt damage the battery. So long as the battery is above 20%, I think itd be good to let the driver have a little more control if they so choose.
What you are asking for and you are not the only one BTW, can be easily done by telling the car where is you home base on a NAV system and what is your trip. You could have preset (like daily commute) and custom trip (From A to B) and let the car decide the most optimal operation and plan for a full recharge at the home base or B destination. As far as I am concern, I prefer the car to decide what is the most optimal operation, but knowing your route the car computer would make the best decision.
 
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