[Timson28]

Hello,
For my thesis I am researching the range of an electric car. Now I am researching different batteries and also at different temperatures. I noted the tension at different times and graphed it. What I noticed is that there is a sharp drop in the beginning and the end and remains fairly constant in the middle. Can someone explain why this is.

thanks in advance

[Corribus]

First: You should explain exactly what you are plotting - dependent and independent variables, with units - and how those values were measured. Second: Ideally you would show data versus just trying to describe it. Finally, part of writing a thesis and certainly doing research is thinking about the data yourself and trying to come up with a plausible explanation for it. Sometimes this requires doing a lot of research into prior literature. If we explain your data for you, then you don't learn anything about the scientific process. If you want to propose something and get feedback, that's where Chemical Forums can help.

[Orcio_87]

@Corribus

He is plotting time of discharge of car battery (or simply - car range) vs temperature.

@Timson28

At higher temperatures metal resistance increases, this lowers effectiveness of battery.

As of lower temperatures I think that results from lowered electrolyte conductivity (that what is inside the battery).

[Borek]

I noted the tension

Do you mean battery voltage?

Google Nernst equation - but you won't be able to apply it without understanding basic electrochemistry/stoichiometry concepts.

[Timson28]

Yes I mean voltage.
I'll look up Nernst's equation.

thanks for the information.