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Discussion Starter #1
I was thinking about putting a large pack in my insight to run with constant assist when cruising, to hopefully stay in lean burn at higher speeds.

I was wondering if the Prius plug in does this? If it doesn't why not?

Would it make any sense to run a car with both gas and electric at the same time for long distances?
 

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I was thinking about putting a large pack in my insight to run with constant assist when cruising, to hopefully stay in lean burn at higher speeds.

1) I was wondering if the Prius plug in does this? 2) If it doesn't why not?

3) Would it make any sense to run a car with both gas and electric at the same time for long distances?
1) No, 2) why would it? The goal of the PIP is to provide a short no-gas range for optimum efficiency.
PIP has an all electric range, then it behaves like a typical hybrid once it's exceeded.

3) Not really. Have you run the numbers on how much battery you need to supply this "constant" assist? You should.
 

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Discussion Starter #3
Then why are people wanting to use the Linsight to run a constant assist while cruising? People are showing they can get 150+ MPG doing this.

Is it not beneficial to do this on an insight?
 

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1) Then why are people wanting to use the Linsight to run a constant assist while cruising? People are showing they can get 150+ MPG doing this.

Is it not beneficial to do this on an insight?
1) Because the tiny electric motor on an Insight isn't up to the task of full propulsion, so using it to supplement the gas engine is the only practical solution IF that's what you really want to do.

Mudder's example in this post:

http://www.insightcentral.net/forums/modifications-technical-issues/82201-focus-group-drop-lithium-cells-use.html#post899617

2kW (2.68hp, about 20-25% of the energy for straight and level typical highway cruise) for 4 hours = 8kWh of energy.

The Insight battery contains 0.936kWh of energy TOTAL. that means you need a battery with 8.5X the capacity of the stock Insight battery. If you want it to last, you have to reduce the DoD to something along the traditional 80/20% SoC limits, so now your capacity is 13.3kWh or 14X the capacity of the stock Insight battery.

Additionally, while I regard the IMA motor as robust, low utilization for long periods of time is exactly NOT what it was designed for.

I doubt you're going to get anywhere near that capacity with your bike batteries.
 

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Discussion Starter #5
actually my intended 3500 MAH pack would be 47s25p would give me 14,100 KW of energy.

would weigh 130 lbs.

I'm not going that route anyway right now. I don't need to drive that many hours in a row.
 

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actually my intended 3500 MAH pack would be 47s25p would give me 14,100 KW of energy.

would weigh 130 lbs.

I'm not going that route anyway right now. I don't need to drive that many hours in a row.
kW is a measure of power, not energy. 14,100kW is a massive amount of power.

So, you have 47*25 = 1,175 cells?

1,175 cells * 3.5Ah capacity each = 4112.5Ah

4112.5Ah * 3.6V nominal = 14.8 kWh energy.

Using the best specific energy reported on wiki for Lithium, it could weigh as little as 122#.

Sounds like you're on the right track. Good luck.
 

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Discussion Starter #7
I decided I am not going that route anyway. I didn't like the cycle life of 3500 MAH cells.

Well, maybe down the road I would consider it but not for my first pack, especially when I don't know how the Linsight will be.

I may put in a cheaper, heavier Lifepo4 pack. But it would only be 8 KWH but cost under $1000. Heavy at around 170-180LBS.
 
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