Hybrid? Just a thought.

[daxwert]

Hi.
This is just a thought. So no flaming please.
Thinking about the need for additional power in my '02 HZJ79 I realised I only need the power for highway overtaking and short steep climbs.
So here is the idea: A highpower (equiv 100HP) electic DC motor connected directly to the driveshaft. a small batterypack (144v 10aH) 'only needed for short bursts up to 1min' and a controller triggered by kickdown. Charging when coasting and braking.
Rough overestimate say its gonna cost me about 3000$-5000$ US which is the same and less as most turbo or engine swaps. No additional electronics to deal with. Save for watercrossings. Additional power source for my camping gear.
Ok. Let me not bore you. Any thoughts?

 

[roscoFJ73]

Interesting. How will you join the electric motor to the drive shaft?

Personally ,I would prefer the turbo,its at its best for overtaking

 

[daxwert]

Driveshaft would pass through the electric motor through adapters. It basically gets a section removed.

 

[amaurer]

I've had this thought before... and then I slapped myself.

Motor in the driveshaft would just spin itself in a circle. You'd need to add some sort of mount to secure the motor to the frame or some such, while not restricting suspension travel. It'd be a total hack job.

But thats not even the big problem - 144V@10Ah = 1.44kWh. In a perfect world, a 100HP motor would drain this battery in 70seconds. In the real world, no more than 70% of that battery capacity is usable, so its really more like 50 seconds of "boost" per charge, after which a 120A alternator running at full tilt would take an hour to recharge it.

Lot of work, $, and equipment for s***ty performance.

 

[seapotato]

there's a vid online where a guy did something similar in a little s***box neon or something.

he converted it to a small diesel , and had a fairly large elec motor mounted on the front pulley of the motor. vid's online somewhere. I think I posted a link to it in the alternative fuel section a year or so ago, look for a diesel electric post.

that said, this was a light little car, not a heavy ass cruiser, and it wasn't mounted in a driveshaft ... I'm with amaurer and giving yerself a slap to be honest...

 

[roscoFJ73]

Lexus seem to have it sorted out

LS 600hL Performance - Lexus Australia

 

[daxwert]

Am Back.
Ok. By straight to the driveshaft I did actually mean mounting it. Looked under the cruiser and did some measurements with specs from suitable motors and I wouldnt loose clearance. The 50 second boost is enough for what I need. Did the maths for 30second boosts. Am still thinking and realised half the voltage for double the amps would also do. Another thought was to connect the turbinesection of a turbocharger to a bigger alternator(motor) to act as free charging by using the exhaust fumes. That offcourse would make a general turboconversion cheaper again. Saw another truck some time ago with a powerfull motor connected insted of the starter.
Thanks for all your input. I havent left the drawing board yet.

 

[sandcruiser]

is it possible? Sure.

But a turbo should be less than $4,000 to fit, more reliable, less ongoing costs (those batteries will wear out) and you should get more performance over a large range of your power band instead of just 30 seconds every hour.

Cool factor? I'd be more interested in looking at someone's fancy electric motor than yet another turbo. But that doesn't get you down the road any faster.

 

[Rusty Phillips]

not an automotive engineer, nor did I stay in a holiday inn express last night....

put down the bong and step outside into some fresh air


j/k - my two cents

depends on what you want to use vehical for - primarily long distance steady state (highway miles) favor diesel with no regen system, if you need more power add turbo or propane

in town or city driving with stops from 40 or 60 to 0 give plenty of opportunities for regen braking but at a cost

turbo has less weight, complexity, and up front (and lifetime) cost, and Id suspect have more reliability & owner satisfaction over the lifetime.

Now - instead of adding electric drive to an already existing 4x4 system - if you instead wanted to do an electric drive system for (front or rear axles) with conventional diesel drive for the other end of car thus giving a hybrid electric all wheel drive system (two 50 hp electric motors built into two of the 4 brake hubs)
with regenerative braking providing bulk of charging (and small charge coming off of diesel engine) then maybe weight penalty would not exist... but upfront cost would be significant, and Id suspect performance (accel, mpg, off road perf, whatever you want to measure against) not terrific

no matter how you do it - batteries big enough to store enough juice (to make any difference) are going to weigh a lot

 

[amaurer]

The 50 second boost is enough for what I need. Did the maths for 30second boosts. Am still thinking and realised half the voltage for double the amps would also do.

Well there are more problems with this idea than that. Basically it all comes down to there being no small way to do an electric car or a hybrid, you either carry enough batteries to "go big" or you just "go home". 10Ah is just too small; even if you're prepared to have such short and impractical boost time, a typical, affordable, battery of that size can't deliver energy fast enough.

A good rule of thumb, in terms of availability and your battery's longevity, is to limit the discharge rate to 20x the capacity (ignoring the atrocious conflict of units), so a 10Ah 144V battery can discharge at up to 28kW, or about 40HP max.

Trading voltage for current will only make the problem worse, if you actually intend to hit 100HP you need a battery about 3x as large.

Of course we're assuming 100% efficiency at each stage.. which is not reasonable.

 

[daxwert]

Ok.
My thought is this. The car is slow. Cruiser mainly used for longdistance cruiseing. Got a Cooper for town. Am currently quite happy with the car at cruising speed. 120 is our speedlimit. Normally have the speedo at 130. Problem is the lorry I want to overtake and the 500m incline which makes the speed drop to 100. So its really just those two situations where i sometimes wish I had more. My mom got the 200VX which I drive exactly the same way and I tend to feel it has too much power unless I'm playing in the huge sandbox.
A weightpenalty of about 100-150Kg is not much in relation to stuff others carry around.
Propane was a thought but refills are quite expensive here.
I have done some research on cost and a 'simple' setup will not be much more.
The wheelhubmotor story has been looked into but those buggers can buy me another cruiser.
Am still researching but it really seems doable. Hmm. This is good s***

 

[daxwert]

Well there are more problems with this idea than that. Basically it all comes down to there being no small way to do an electric car or a hybrid, you either carry enough batteries to "go big" or you just "go home". 10Ah is just too small; even if you're prepared to have such short and impractical boost time, a typical, affordable, battery of that size can't deliver energy fast enough.

A good rule of thumb, in terms of availability and your battery's longevity, is to limit the discharge rate to 20x the capacity (ignoring the atrocious conflict of units), so a 10Ah 144V battery can discharge at up to 28kW, or about 40HP max.

Trading voltage for current will only make the problem worse, if you actually intend to hit 100HP you need a battery about 3x as large.

Of course we're assuming 100% efficiency at each stage.. which is not reasonable.

I get your points. Been doing some reading since that post. actually turned around the figures. Am currently looking for a cheaper source for these to ensure discharge rate and quick recharge.

What I want is basically the lexus/prius setup.

 

[sandcruiser]

I say go for it!

Personally, I'd just turbo it and be done for all the reasons posted above.

But if you want to spend your time/effort/$$ on going semi-hybrid, I'd love to see the results. Who knows, down the road it could spur something practical. Tinkering is fun.

Somewhere out there there's a guy who adapted a jet turbine to a VW bug. Not practical at all, but pretty darn cool (and it would give you that passing power you desire)

 

[amaurer]

I get your points. Been doing some reading since that post. actually turned around the figures. Am currently looking for a cheaper source for these to ensure discharge rate and quick recharge.

What I want is basically the lexus/prius setup.

Definitely get some more specs on those batteries before you plunk down lots of coin - 70% discharge is allowable for a "deep cycle" lead acid battery, but would be way too deep for many other types of batteries. The batteries you link are absolutely not designed for deep cycling, they're peaker batteries for smoothing out ripple - depth of discharge ratings may shock you (maybe as low as 10-20%).

All the nay-saying aside, I've always wanted to get my hands on a spare semi-float axle and see about attaching a second third member to the back side where the diff cover goes. Naturally you'd have to remove the diff, ring, and bearing mounts, and it'd be damn near impossible to get it aligned perfectly... but maybe, just maybe, good enough to do the job for short bursts?