[Clarent]

Any more details about it? When you say screen flashed, can you remember what it shown?

You've mentioned the battery, so that signifies it's a laptop, but do confirm if that's the case.

The best thing you can do right now is to unplug it completely (if it is indeed a laptop, remove the battery) and get it to a specialist who can maybe salvage something.

If it's just the battery that's dead, getting a new one should be all that's required (assuming it's a laptop).

However if a motherboard got hit as well, I'm afraid you shouldn't expect good news. Even if you managed to drain it, its likely the initial blast was more than enough to kill it (and if it wasn't, the turning on and off propably was).

Absolutely do not try to turn it on by itself anymore. Motherboard be damned, but if the supply unit got splashed as well, starting it is incredibly dangerous.

As mentioned, get it to a repair shop. Maybe something can be salvaged.