[cousin_it]

I don't imagine using explosives for it. More like one ship is a railgun and the other a projectile. Then when they meet again, they can convert their leftover relative velocity back to electricity, by having the railgun catch the projectile and charge up.

Or the two ships could be a spinning pair tied by a cable, and then the cable is severed. To make a fast spinning pair, start two spinning pairs in parallel planes and opposite directions, and make them accelerate against each other electrically.

There are probably objections to those too, like size of railguns and strength of cables, and then engineering can find answers to that, and so on.