Next Gen Plug-In

We have heard nothing about it.

Anyway, let's assume following scenario based on the press release of current field testing version.

The full battery capacity is 5.2 kWh, 100% SOC (ceiling).
The usable battery capacity is 3.56 kWh.
Let's assume the full charge is finished at 100% SOC, and the initial charge-depleting mode is done down to 32% SOC or 68% (3.56/5.2) DOD (depth of discharge).
Then, it goes to charge-sustain-mode to maintain 32% SOC for the rest of normal hybrid driving.

The current Gen3 Prius' target SOC is 60% (six bars) and the full SOC is 80% (eight bars:ceiling), then there is only 0.26 kWh (20% X 201.6V X 6.5Ah) space available for the downhill regeneration.

So, it depends on how much capacity you have remained to the ceiling.

If you just finished charging (100% SOC) and you started driving downhill, there is no space available to store regenerated energy.
If you were driving in charge-sustain-mode (32% SOC), you will have 3.56 kWh (13.7 times as much as the current Prius) space available, I hope.

Ken@Japan

 

Unfortunately the best/lowest cost battery technology has a long way to go to match the energy contained in a gallon of gasoline.

The Nissan Leaf lithium-ion traction battery currently is rated at a capacity of 24 kW-hrs (32.2 HP-hrs) Nissan LEAF Electric Car | Battery | Nissan USA. I cannot find any data on the weight of the battery, but I imagine it is several hundred pounds.

Compare that with the energy equivalent of a US gallon of gasoline, which is 36.3 kW-hrs, or 48.6 HP-hrs. So the Li-ion Leaf battery stores the equivalent of just under 3/4 of gallon of gas, weighing just under 4 lbs, and takes 16 - 18 hours to recharge at 110V, or 8 hours at 220V.

How long does it take to put 3/4 gallon of gas in your tank?

Conversely, to put the equivalent amount of energy contained say in a Prius gas tank (call it 10 USG), into the Leaf traction battery (you can't of course, but if you could) would take 121 hours, or just over 5 days charging continuously at 220V.

This illustrates the challenge facing the electric storage/battery technology companies. Don't get me wrong, I am fully behind the furthering the art, electrical motor power is considerably more efficient than any ICE. But getting the stored energy density much closer to that of gasoline is key to the spread of all electric transportation.

 

Your post highlights big advantage of EV technology.
If this car really gives 100 Mi range, it is equivalent to 133 MPG. Event if you consider 50% efficiency of energy generation and transport it is still 67/MPG. But then you should consider energy consumption in refining and distributing gasoline for fair comparison.

24 kW-hrs = 100 Mi means about 4 Mi / KWh. That is about 3-4 cents/Mi. That is about half of gas costs as compared to Prius.

Also consider maintenace costs. I believe All electric car should have very minimal maintenance. We should be able to do away with oil changes and such. Typical maintenance interval can easily be 30000 Mi.

100 Miles range should be adequate for most. I would be much better off renting on occasions when I need a longer range. Or use another bigger car/van/suv as many of us have as a second car for longer drives.

I would be eager to try EV technology. My main concerns are

a) How does battery life deteriorate over time?
b) What is battery life and battery cost?
c) Do money saved in fuel offset increased expense of replacing battery? ( I imagine deep discharge batteries would have a usable life span of 3-4 years about 1000 or so cycles.)

If 100 Mi range become 50 Mi after 300 or 400 recharges, the battery is useless for many.

 

ronhowell, the Leaf batterys are said to weigh in at 450 pounds or so, and are mounted below the seats.

You can't just compare the energy density of gasoline vs stored electricty, as only about %20 of the energy of a gallon of gas goes towards motive force in a vehicle. A much higher percentage of the battery energy is going to motive force in a BEV.

and yes, the Leaf with it's 24KW pack is supposed to have a 100 mile range, so 1KW to about 4 miles. Comparing that with a 50mpg Gen3 Prius, looks like 2 gallons of gasoline (in a Prius) = a full leaf charge, but that is 2 less gallons that get burned, if the power source that charged the leaf was non-fossil fuel based, such as solar or wind.

 

Thanks Ken

Some interesting information.

With more battery capacity, it would be interesting to find out also if the car will be run in the modes of the current model. That is - to *not* run it in EV mode unless asked for. I'd guess in some situations, running in a mode like ECO where you are under battery assist, rather then pure battery, you might be able to get better mileage then if you run off of pure EV mode for the first 13 miles, then in some hybrid mode afterwards.

Who knows what the best driving modes would be - or if the best modes would depend on the terrain and distance of the trip - but it sure would be fun to have the ability to play with it to see how well you could do.

 

I can understand what you are saying.
We have discussed about the requirement of a forced hybrid-mode (charge-sustain-mode) switch on the following thread.
http://priuschat.com/forums/prius-h...le-range-1-5-hour-recharge-7.html#post1018617

Ken@Japan