new guy thinking about building an EV.

[crxls]

A few years ago I read an article about a guy that built an electric truck with a bed full of batteries. I thought the idea was great but I was over it as fast as I read the article. Now just the other day I somehow stumbled upon this site and started reading about all of your EV conversions. I was shocked to find a lot of you doing these conversions on such small budgets. This also got me to thinking. I have a 93 Honda accord manual transmission DX which has manual seats, mirrors, locks and Windows. Weighs in at just over 2700 pounds. This car has 268,000 miles in it and is now in need of an engine replacement (which I have already). I know this isn't the ideal car to do this EV conversion to but it is what I have to work with at the moment and would love to do this. No, I'm now determined to do this! It will mostly be a dedicated drive to work car. I live in southern Pennsylvania and my commute to work is 25 miles each way with some hills.

I'm good with cars but a lot of your electrical terms have me completely lost. I can fabricate anything needed and put everything together but will need help knowing what parts to use. I would love to hear some of your suggestions on what route to go here. What I have in mind us a basic cheaper setup that will work for my needs to start with and then over a coupme years time upgrade to better equipment.

If this is a success for me, I'm sure we will then put together an EV for my dad and a few friends with shorter commuted also.

[Ryland]

EVAlbum: Vehicle Types and Makes
Is really the best place to start, look at vehicles of the type you have and see what others have done and how much they spent and troubles they had.
My big suggestion is, don't build a car that has a 25 mile range if you need to go 25 miles and if your 25 mile range is at 80% discharge then you will kill your batteries in just a few years so make sure that you are above 50% discharge in your daily use with a stop or two on the way home and you will get the most life from your batteries an you will use your EV for more trips.

[MPaulHolmes]

Awesome!!! The funnest thing about driving electric is sitting at a stop sign and it's just dead silent. I've had people come up to me to ask if I needed help, and then I drove away. It was so much fun! Well, it's also fun getting a full tank by sticking in a power cord in the wall. You can definitely do it cheap, but 50 miles is quite a bit of range for Lead Acid.

[crxls]

I can plug it in while I'm at work but would much rather make the round trip on one charge if possible.

I know that 12, 12 volt batteries will give me 144 volts but I don't know how that compares to 6 batteries that would give me 72 volts. Does more volts give you more power or longer lasting power?

[MPaulHolmes]

The car uses a certain amount of energy per mile. Like 200 watt*hr/mi if it is SUPER efficient and aerodynamic. And like 500 watt*hr/mi if it's a big fat truck. The battery pack stores a certain amount of energy. But you have less usable energy available from the pack the more current you draw. It's called the Peukert effect. So you want to keep the amps as low as possible. Voltage*current is power. For example, you can either do 100 amps at 72 volts or you could do 50 amps at 144 volts at the same power level.

Lead acid battery packs will have more amp hours available at 50 amps than at 100 amps. Long range with lead acid is usually done by lots of 6v batteries. Like 120v or 144v worth.

[mechman600]

I'm in the same boat as you. I have researched EVs till I was blue in the face. I go through phases where I am ready to pull the pin and drop thousands on motors, controller and batteries, and then a few months go by as if nothing happened. I can't speak from experience, but I think I am well versed in "EV theory." Much of what I have learned is from DIY Electric Car Forums Site Home , a very good forum to go through. So much info it will scare you. The guys there are ridiculously helpful and even the simplest questions do not get ignored.

I could get into theory and numbers and whatnot, but I will save time with this link: EV Calculator

Punch in your numbers and play around with it. It will give you an idea of what you need to use for the EV you require. A very impressive tool.

[Ryland]

Basic brake down is, higher the voltage the faster you can go, more watt hours in your battery pack the farther you can go, so looking at EV design calculators you can get a good idea of what you need to reach the goals you want, then looking at EV albums and you can compare that to what other people have done and see if it worked out as planed.
There is also very little harm in going with a higher voltage because a higher voltage will stress each battery less, it will have fewer amps total on the battery cables so you can either go with smaller cables or have less line loss and when you do need that slightly higher speed it's there, the rest of the time it's not being used, the big draw back is more batteries and sometimes it bumps you up to a more costly speed controller, but most speed controller have a voltage range that they will work with so I say go for as high of a voltage battery pack as you can with while still using traction batteries, these are batteries designed for the high loads of an electric motor driving a vehicle, not the lower loads that a deep cycle RV battery might see.
Ben Nelson (on this forum) sells a rather good Build Your Own Electric Car, Cheap! DVD, well worth buying.

[como]

crxls,
I'll be watching your progress closely. I recently aquired a 1990 honda civic with a dead ICE- I'm doing a slight rebuild to get it on the road, but in another year or two that engine will be gone for good, and this is the smallest, second lightest car I've ever had, so I'm excited to start collecting parts to make this happen.
I've also got... 6 cars outside, 5 of which run, 2 of which are for sale... so I've always got a spare care handy should my project fail on me.

My target range is shorter than yours, but I get the feeling we're working on the same budget