Battery Vehicle Society

Hi All, I am new to the EV scene, I am an engineer who tackles anything that interests me. The reason I am raising this post is to ask many questions, what is involved in creating a road safe DIY EV? If I purchased a small saloon/estate car removed the ‘lightweight’ engine and created a practical EV, I need to do a round trip to work of 40 miles on a charge, most of my journey is 30-45 mph I have a 6 mile stretch that can be avoided but if not I need to reach 60mph . What will this cost me to convert what ever requires converting to ‘go the distance’ and enjoy many a happy/reliable mile
Also how involved will I need to get with the Electronics, ie is this a ‘plug and play’ chip set or a ‘rocket science’ hadron minefield of technology. Thanks in advance for any replies

One word P.C.H...............Berlingo

TBH I've done the DIY route and 40miles range is hard work unless you spend a few quid on Li-ions and 60mph is going to be hard to get with that sort of range.

Buy a berlingo and its a plug and play route, you plug it in to a 13a socket and then when its charged you play with it

ChrisB

If your needs are for commuting to and from work, so that two seats only and limited luggage space is acceptable, then you may be better looking at converting something small and very light weight, like a kit car.

Going down this route can make things electrically straightforward (off the shelf parts are fairly readily available), albeit at the expense of more mechanical work. It depends where your skills lie really; if your happy fabricating mechanical bits and pieces then the kit car route might be a reasonable choice.

Motors, controllers, throttle pot boxes, fuses, cabling etc are all pretty much "plug and play", as is battery fitment and cabling if you stick to lead acid batteries. Although lithium batteries offer much enhanced capacity for their weight, they absolutely must be fitted with a decent battery management system, which complicates things a bit.

The key to getting the performance and range you're looking for is to choose a base vehicle that has a small frontal area and good aerodynamics for reduced power requirements at speed, plus has a low basic weight and enough space for a decent size battery pack. Weight and aerodynamic drag are the two critical factors that hit EV performance hard, due the relatively low energy storage capacity available from current battery technologies.

Jeremy

Although lithiums add electrical complexity and cost, they save you some money in other areas. The weight savings mean that you don't have to upgrade suspension components, for example.

If you need to make a 40 mile journey on a charge, your car will need a range of 60-80 miles to maximize battery life. Also this gives you a buffer if you suddenly find that a diversion has been setup on your route, taking you the "long way around". Now if you can convince your employer to install a charging point at your work then your 40 mile range would be adequate as you will only be doing 20 miles on a charge. Even if you subsidized the cost, it would probably be cheaper than the bigger battery pack.

But keep an eye out for a Berlingo as well.