EV range and performance?

Looking at buying a new 2004 Prius but a couple of questions

In EV mode...

What speed can be maintained? Will it drive around town just on EV and not embarress itself?

How far can it travel on EV

Reason for the questions are that I have two sets of journeys - one is 25-30 miles on fast roads at 40-60mph and the other is a 5 mile trip into town where I never exceed 30mph.

Would be nice to consider that I could do the town work solely on Electric power and recharge the batteries on the faster runs.

Also, does anyone know if aftermarket battery charges are available? Perhaps running from a wind charger (we live on the coast!!)?

Thanks

Scorpio

 

Thanks for the info.

We are UK based so we get the EV button as standard. 3 miles is a heck of a short distance though

As I understand it, the battery pack is a stack of 130 or so D NiMh cells which are packed in a matrix of Serial/Parallel mode with temp sensors and a couple of cooling fans.

It is quite simple to obtain NiMH D cells from surplus outlets and we can generally pick them up here in the UK for around 50p ($1) apiece in bulk.

Therefore building a battery pack that will lie in the floor of the boot space and approx 4" deep, complete with temp sensors and switchable cooling fans is quite practical and certainly possible for a 2KWH unit to be built for around $700 or so.

Could such an item not be installed in parallel across the existing battery pack? Does the CPU use voltage sensing to determine charge state etc and would additional capacity therefore be compensated for (in the same way that it senses a dying battery pack).

I'm fully aware of all the safety precautions etc of working with NiMH and high voltages.

Thanks for your help so far

Scorpio

 

Many thanks Evan

Any further info would be most helpful.

Bear in mind that I am after extra range and not speed - 35mph is more than adequate for our needs.

If the EU version includes an EV button then surely there must be sufficient lubrication already built in to the system. After all, Toyota doesn't say anything like 'Only use EV for 2 miles' or similar and they don't know that I don't live at the top of a mountain with a 10 mile downhill ride into town.

Just a thought.

We can buy those NiMH D cells very cheaply through military surplus routes - they come complete with solder tags etc. They just need testing before usage as 1 in 10 is generally faulty.

Thanks again

Scorpio

 

That's interesting.

However the EV button can be used when the vehicle has not been driven using the ICE - say after a lay-up of 2-3 weeks when any lubricating oil has drained or dispersed. So operation of the Electric drive would result in no additional lubrication of the ICE or the epicyclic gearbox. However my very limited experience of such gearboxes is that they are 'sealed for life' units and hold their lubrication internally.

The problems could arise if the ICE was spinning during EV use - although then I would imagine that the crankshaft driven oil pump would circulate lubrication oil throughout the ICE.

If I am not understanding the issue correctly please tell me. What other lubrication is needed other than ICE or gearbox?

Thanks

Scorpio

 

Just re-read the application and I think that the vehicle actually handles the issues of lubrication by calculating the time since the ICE was last used and the various system temps and then using a map of the viscosity index of the oil (NOTE: ALWAYS use the recommended oils or else!!) to determine whether additional lubrication is needed. If it is then the Electric motor spins the ICE at idle speed so that the crankshaft oil pump circulates the oil for a predetermined time.

It's interesting that earlier in the application they refute the use of an Electric oil pump because it lowers the engergy efficiency - however they then advocate the use of the ICE being spun by the Electric motor to circulate the oil - that's really not efficent and will accelerate wear on the ICE - imagine the energy being wasted.

More likely is that as the ICE is a standard 'off the shelf' engine which already has a built in oil pump, then they decided to use the method of spinning the engine when lubrication is needed. But it's a bit unfair to claim in a Patent application that they chose not to use an electric oil pump because it would be inefficient.

The only real question is whether the software algorithm in the ECU calculates the oil lubrication requirements over an indefinite time period - my guess is that it probably does for my previously outlined scenario - top of mountain downhill to town.

Scorpio

PS Sorry our posts overlapped - I'm sitting tight

 

Thanks bri1600bv

Normally the calculation of remaining energy is done via voltage drop and (I am hoping that) adding additional battery capacity would be taken into account automatically by the sensing system in the same way that the ECU must account for the wear and tear in the batteries over say 7-8 years when their storage capacity may only be 60-70% of a new battery pack.

Scorpio

 

Nice diagram

Slightly confusing in that it shows a seperate oil pump on the opposite side to the ICE - whereas the patent application refers to the use of the crankshaft driven in sump oil pump in the ICE being used to supply pressurized oil.

The diagram seems to show an oil pump that is driven by the electric motor shaft at all times that the electric motor is spinning which would mean that in the Prius, there would be no need to drive the ICE when in EV mode.

Does the Patent application actually refer to the Prius? It would appear that the modus operandi of the Prius is different to the Patent.

Scorpio

 

Well I went to drive my first 04 Prius on Sunday and the quick answer is that 1 mile is about the limit. There is some great space under the rear trunk floor for an extra set of batteries but even filling that looks as though it could only extend the range to 2 or 3 miles at a cost of over $1000 - just not worth it.

I don't think that the current battery technology used on the Prius can ever get to the ideal 25 mile @ 35 mph that we are all (probably) looking for - a bunch of lead acids in the trunk might just do it (joking)

I seem to remember the last time I was in the States that there was a Saturn EV - looked a bit weird parked up at Frys plugged into their free charging station - anyone have any info on that vehicle?

Anyway, I've put my order in for the Prius - Feb delivery for a T4 due to 'unprecedented worldwide demand' according to the dealer - oh and no discount off the MSRP

Scorpio