208km (129 miles) in electric mode with a gen 2 prius

all

It was a challenge. Going to the nearest beach and back without gasoline and without pluging my car during the trip.
Theorically 101 km (63 miles) one way and same back. But some road where closed and finally 208.2km (129 miles) where done.

I use a main pack which have 140 A123 20Ah, (I also keep the stock nimh pack), and a third pack made with 936 LG 2.8Ah 18650 cells.

The A123 give the power, the LG increase the range.
The A123 weight is 80 kg ( 176 lbs) for 9kWH, the LG 45 kg (99 lbs) for 9.8kWh.
But the LG are energy cells, not power one. So I add a dc-dc converter between the 2 packs in order to control the amperage and then the 2 pack voltage can be different.
The total is 20 kWh.
The lg pack have a lower voltage then the A123, so a dc-dc converter (meanwell) is added to boost the voltage and control the amperage. It was under 10A during this trip.

I used 16.7 kWh so the average was 80.1 Wh/km (129 Wh/mile)

This have been possible because I improved my car aero and used LRR tyres (Toyo nano 2)
Aero mods are:
Full underbody panels
Wheel covered
Front Grill blocked, keep just a small slot
Rear wheel squirts
Replaced 12v lead acid with 4xA123 20Ah+capacitive bms


Inside the rear of the car, not final design:

On top the LG cells just over the nimh.
Same level then the nimh, the A123 some are in the spare tire.

All in OOG mode, the more efficient one.
Average speed was 46-47 km/h (29 Mph), top speed 85 km/h (53 mph)
Max ev power 32kW ! Max regen 28 kW. 33% energy regen when going to the beach and 20% back.

I enjoyed this trip.

 

The first would be to remove the nimh cells and then replace with 30kg (66 lbs) LG cells.
This would add 6.5 kWh (more then 5.5 kWh usable) so 69 km more (43 miles)
Second you can remove the spare tire, 10kg then add 23km more (14 miles).
After this I would drive during summer, hotter air, give better mpg. When i drove the temp was 20°C.
Then I would use a road that I know, in order to reduce the regen. Because the more regen you have the more losts.
If you have more money, you could replace the LG cells 2.8Ah with Panasonic one 3.4 Ah, same weight.
You could also add a boat tail, replace rear side mirror with camera

....

And finally remove the engine, but before driving

 

Hello elman1. I don't sell anything. Sorry.
I only help diyers. We are 4 diyers here in France using this plug-in design.
I use A123 20Ah cells. Have done 4,5kWh and later 9kWh. It is possible to have 13.5 kWh if you remove the spare tire.
9 kWh weight 80 kg. 13.5 kWh would be 115-120kg. You can have 4.5kWh in the spare place and 9kWh over.
With the 9kWh I haven't changed the rear spring. With 13.5 kWh it will be necessary.
You have pictures in my album

If you use A123 20Ah cells, because they have a very small internal resistance (except in winter) it is not necessary where I live.
With the 9kWh version, the cell temp increase is about 10°C during a trip. So begining at 30°C you end with 40°C. These cell must be used under 55°C.
You may have temp problem if parked in a sunny place in summer. Temp can be very high in a car.

In summer I have to add a small ventilator over my charger (Elcon 2kW) say 2-3 times in the year.
If not his amperage is automatically reduced and charging time is increased (Derating).

I had same problem with the bms. You can have more infos in this thread.
This bms have a ttl bus that have to be the shorter possible.
No problem on the power circuit. No problem with bms+

As far as I know, pluginsupply use contactors that are opened/closed during travelling and use a lithium pack that have a highter voltage then the nimh.
I have a contactor but it stay closed during all the trip. It is opened only during grid charging. The lithium pack have the same average voltage then the stock nimh. That is wy I use 70 A123 cells not more not less. You have full regen power, except with the 4.5kWh system and cell temp under 0°C.

If you remove the stock nimh cells you can use bms orion system and more then 70 lifepo4 cells.
I meet a diyer that have not used A123 cells but only 18650 Limn.. cells. Total 16kWh. He came from belgium.
In France a society use Winston cells.
Both use orion system. Both changed the rear springs. Because cells weight and also because they don't leave any space behind the cells.

You are welcome.

 

It depend upon gasoline price and electricity price. Here in France driving in ev mode is 5 times cheaper then with gasoline.
Engine will last longer.

 

Kristoffer

I have 10 or 20 kWh inside, depending on the length of the trip. So I use my car like en ev car (Last week I drive 380km, 235 miles, in one day with three charge). Last tank fuelling was last year, 11 month ago. During this time I drive more then 12 000km ( 7450 miles). I use the engine once a month, just for lubrificating or if I don't have enough electricity for one trip. I will change oil this year, haven't changed it in two years. The color of the oil is still yellow.

My Prius has become a very efficient ev car with a very good Cx (0.22), not too heavy. 110 Wh/km from the plug in ev mode.

 

I still use 5w30 oil. Not sure 0w20 would be better for an engine that don't run. Does somebody knows ?
I don't have a good knowledge of oil properties. I think that some part of the engine could rust. MG2, MG1 and the transaxle are still oiled in ev mode. But there is some evaporated part of gasoline in the admission air intake, even after a very long time in ev mode. If you open the air intake filter, it smell. I suppose this gas come from the tank (we don't have a bladder in our prius) when outside temp increase.

@bisco, 124 miles (say 200km ) seems to me a very short time (with for exemple an average speed of 50 km/h = 4 hours). What happens if we don't use our car during several months ?

Concerning gas I only add 10 liters last year., less then 3 gallons. In my country we have many more public plugs, but they can be out of order, some can be used at any time others no.
So my prius has become more a ev car with a gasoline range extender then a gasoline car with a battery extender.