As per title, can be connected permenantly so your battery's always ready,

A fiver in Lidl's at the mo

or a cheap electrolysis charger maybe?

I can't see any listed at the moment.
Linky please?

I doubt these would be effective for electrolosis. They supply small amps but longer periods of time hense the trickle part!

<----Edit---->
Unless you mean charging a battery up, then electrolosis, then charging. But still trickle chargers are only meant to 'top up' batteries not recharge them.

[Edited on 21/707/0707 by JamJah]