Depends on the way your animation is made, but you could:
(A) Change the play rate of the animation. Is animation time is 1s, and at 0.5 it should reach the top, but you want it to reach the top after 1s, use a playback rate of 0.5.
(B) Split the animations into parts while looping (or changing the play rate) of some animations. Usually common in jump animations where you have an animation before jumping, while in the air, and for landing. You just move from one animation to the other when you want to, and you can loop them.
The second option will give you more control over the overall look, but it will require more animations and more work probably.
Changing the play rate is probably gonna be easier, and if you’re charge won’t vary too much (animation-wise), it should look good enough.