About electric car battery weight

Hello all , I am a HEV enthusiast from India . I love electric cars and I am planning to build one on an experimental basis . My question to the forum is concerning weight of batteries . If the batteries were kept in a separate trailer , would there
be any performance improvement ? many thanks in advance.



No mass is mass, it takes the same amount of energy to move a given amount of mass. If anything it would be net negative because you would have the additional weight and drag (rolling and aerodynamic) of the trailer to overcome.

thanks . I wish to build a small diesel electric car that would be very economical . My experimental car would be a mini hatchback . I am planning to buy a small diesel generator with which I would charge a series of batteries as the car runs . Would this be a sound idea ?

Well diesel is certainly more efficient than gasoline, a lesson dumb Americans have not figured out yet.

But unless you have a design team with all the specialty engineering skills, how are you going to pull this off?

I am looking for a good team here. I can learn through books or other articles in the internet and try implementing them gradually. My country needs an electric car or an hybrid one to curb the pollution levels to an extent . A few companies say that they are about to launch electric hybrid vehicles but, I think the wait is going to be endless . Are there any resources in the internet for me to build a diesel electric car ? There are companies that sell mini diesel gensets .The motor, ac-dc convertion device and batteries are all available stock . All I need to do is to implement an already existing successful formula ? Thanks again .


HEVLOVER good luck to you, you are going to need it.

HEV’s are very specialized complex piece of machinery with heavy computing and integration of all systems to achieve high efficiencies. If designed properly they do have lower emission profiles than their ICE cousins, but only in city stop and go traffic with slower speeds. All that is lost in long distance highway driving.

EV’s on the other hand are the lowest emission vehicles period even if the electricity is generated by coal, and zero if generated by nuclear power.

Good luck


I have heard of zinc air batteries to drive EV. Is this a successful idea or is it still in R&D ? They are light weight and have a greater energy density.


Zinc-Air batteries exist but they are primary cells (not rechargeable).

More than electric , I think the future would be more towards utlizing hydrogen fuel . I may be wrong but , that is what I think now . In car production of hydrogen thru a novel energy efficient photocatalyst that splits water using minimal energy or some sort … Fiction becomes fact :wink: Storing hydrogen seems to be the biggest problem here . Till then batteries and EVs rule the roost . Hope I’d be able build one soon !

A few people have taken the Reva electric car and built them into hybrids using small generators or fuel cells.

There is room under the hood of the Reva to fit a small generator. Alternatively, you could have a generator fitted to a trailer and tow it behind the car for the occasions when you need a longer range - that way when you don’t need it, you are not carrying around unnecessary weight.

The fuel cell system is interesting - to keep the cost down, you build a range depleting fuel cell, so that it extends your range, but eventually the batteries run down and you have to stop. However, when you are stopped, the fuel cell then recharges the batteries again.

EFOY fuel cells have been used in Europe on Reva’s (EFOY-Brennstoffzellen - Immer und überall Strom - EFOY). I don’t know what system has been used on the Reva fuel cell vehicles built in Bangalore.

Incidentally - I’m not telling you to ditch your idea and buy a Reva - I’m just giving you an example of what has been done elsewhere, and it just so happens its been done in India.