SamRich
100 W
Ohbse said:Jonathan1981 said:it would be awesome to find a cheap mold-able material the could do that. I was thinking something like mixing aluminum powder into a soft two part epoxy and molding a thin layer around each cell?..... thoughts, links etc???? just trying to think of a cost effective DIY cooling solution for such a large pack..
Wax. http://www.allcelltech.com/index.php/technology/pcc-thermal-management
Phase change temperature can be varied with composition to target the sweet spot for optimal cell performance/lifespan.
The downsides are primarily mass and complexity. In many circumstances you would be better off taking the mass dedicated to the cell cooling and adding additional active material in the form of more cells. More of the same cell with the same power demands lowers per cell heating OR more cells allows for a more 'power' focused chemistry while hitting your energy requirements, again reducing per cell heating due to lower IR.
Essentially to maximise performance and longevity, you should use the largest possible pack you can package. The higher % of mass of your vehicle is active material (cells OR motor) the higher system efficiency will be in general.
On my latest skate prototype, over 75% of the total weight is in cells or motors. Next one will be even higher. On my bike the proportion is about 60%.
Agreed. I like your way of thinking about the problem.