Does a higher velocity make a collision more or less elastic? Does it have any impact on it at all? Basically, if you increase the velocity before the collision, does the collision become more elastic? If you used conservation of energy as proof, (i.e the faster the velocity, and the less percent of energy lost), does that work?
 A: No, the elastic collision equations can be solved analytically for any starting speed. The collision becomes inelastic when you are also imposing conditions at the end of the collision, such as the two moving with the same speed, etc.
A: One measure of the elasticity of a collision is the coefficient of restitution, which is given by
$$e=\sqrt \frac{KE_{after}}{KE_{before}}$$
Where e ranges from 0 to 1.
$e$=1 for a perfectly elastic collision and e=0 for a perfectly inelastic collision.
If e is a constant then increasing the initial velocity should not change the elasticity of the collision. However it is only a constant for a limited range of speeds. 
In general, for a given object the greater the deformation the greater the loss in kinetic energy dissipated as heat. And the greater the impact velocity the greater the deformation. For small deformations behavior may approach Hooke's law (linear elastic), depending on the  material, and the collision becomes more elastic.
Bottom line: Increasing the velocity before the collision generally makes the collision more inelastic.
Hope this helps. 
