Please help, EVA could not!

Conversion Kits
1

Ok, so my plan is/was to build a 90’s 2wd Toyota pickup into an EV. My requirements are:

[ul]
[li]Top speed of 65-70 (not super important, as long as it’ll do at least 55)[/li][li]Get me to work, and back (12 miles each way)[/li][/ul]

Sounds easy, right? Well maybe, maybe not… There is a 1,200’ elevation change one way on my commute to work (it’s downhill to work). There is a 2.5 mile grade that is 10-11%.

In talking with EVA I got the following proposal:


2008 JULY	ELECTRIC VEHICLE CALCULATIONS	
SMALL TRUCK		PREPARED BY		
ELECTRIC VEHICLES OF AMERICA, INC	
(603) 569-2100		
 				
VEHICLE DESCRIPTION				SYSTEM DESIGN
INITIAL CURB WEIGHT (LB)	 		1. MOTOR	FB1
FINISHED VEHICLE WEIGHT (LB)	4200		2. BATTERY	T125
DRAG COEFFICIENT 	0.4		3. 20 HR RATE	235
FRONTAL AREA (SQ FT)	20		   75 AMP RATE	125
TIRE SIZE			   C FACTOR	0.99
RR RADIAL TIRE	0.01		4. VOLTAGE	144
REV/MILE (HIGH GEAR)	900		5. MOTOR EFF	0.88
6. DRIVE EFF	0.9
********************************	********	********	********	********	********
RESULTS OF	HP		ESTIMATED	RANGE	  (MILES)
CALCULATION	REQUIRED		MIN	AVG	MAX
(BASED ON 20 MPH - 10% GRADE)	28		17	34	190
********************************	********	********	********	********	********
SPEED (MPH)	3	6	9	20	15
-------	-------	-------	-------	-------
DRAG (LBS)	0	1	2	8	5
ROLLING RESISTANCE (RR)	42	42	42	42	42
TRACTIVE FORCE (0% GRADE)	42	43	44	50	47
PER CENT GRADE FORCE + Tf					
0	42	43	44	50	47
0.05	252	253	254	260	257
0.1	462	463	464	470	467
0.15	672	673	674	680	677
WHEEL TORQUE, FT-LBS	*******	*******	*******	*******	*******
0	39	40	41	47	44
0.05	235	236	237	243	240
0.1	432	432	433	439	436
0.15	628	628	629	635	632
REQUIRED MOTOR HP	*******	*******	*******	******	*******
0	0	1	1	3	2
0.05	2	4	7	15	11
0.1	4	8	12	28	21
0.15	6	12	18	40	30
CURRENT REQUIRED (AMPS)	*******	*******	*******	*******	*******
0	2	4	7	18	12
0.05	13	26	40	91	67
0.1	24	48	73	164	122
0.15	35	70	106	237	177
AVAILABLE MOTORING TIME (MINUTES)	********	********	********	********
0	4577	2254	1468	569	821
0.05	758	373	245	102	141
0.1	409	200	130	52	74
0.15	278	134	86	33	48
CALCULATED RANGE(MILES)	********	********	********	********	********
0	229	225	220	190	205
0.05	38	37	37	34	35
0.1	20	20	19	17	18
0.15	14	13	13	11	12
********************************	********	********	********	********	********

With a 144v system using the FB1-4001A and 24 T-125 batteries, it would take 28hp to sustain 20mph up a 10% incline. Since the motor only has 30hp, it just isn’t going to cut it. I’d get run over by a logging truck. :smiley: Edit - I need to be able to do 45mph to be safe.

So what can I do? I have a truck bed (and under the truck bed) and I’m not afraid to use it for plenty of battery.

Ideally, I’d LOVE to be able to drive the truck from work to the next town over for errands which is about 20 miles from work and also very hilly, and back, and then go from work back home another 12 miles. Of course I can charge from both work and home.

Any ideas or help is appreciated. Thanks!

2

My Ford Ranger is an EVA kit with I’m sure the same parts list as what they described and I would have to agree with them. Mine will do fine on speed but when It come to pulling hills it eats power with all the weight. I am running 24 US battery 220 amp 6v batts and I am packing 1500 lbs. It might make it half way if you could charge at work.

Perhaps you could look into lithium although I know the cost is obnoxious to say the least but the weight would be about 1/3 which would make those hills much nicer.

Robert

3

Your range might be increased if you were to use a sepex motor, that is, a shunt wound motor. They have the ability to generate electricity when going down hill which should help you in your hilly drives. The controller selection is not as large as it is for serial wound motors but Curtis make several that can be used. Good luck.

4

I would definately look into a Sep-ex for that situation also. One thing A sep-ex has a flat torque curve. Kelly also has as sep-ex controller that is what I am using. You will need a higher voltage to climb those hills. Since it is downhill to work you can regen the batteries and be fully charged. GO with a 10-11" motor the beefier the better, don’t skimp here for that truck.

5

In your case you might have to step up to Li batteries and big AC motor… Li and a 11" DC would probably be fine too, but you might want that AC regen on the way down the hill!

You sure DON’T want a bed full of 6v batteries. You’d be better with 144v or 156v of 8v, but still very heavy. using 12v would be lighter, but shorten the range and life a lot even with good deep cycles.