This is how to convert a cheap pound store or dollar store solar led light into an electric slug or snail fence.
Electric slug fences provide a barrier to slugs or snails and stop them eating your plants. The voltage used is safe for children, pets and wildlife. Slugs are most active at night, so the operation of the solar light suits this purpose very well. In fact there is one commercial unit that operates in the same way, but at a considerably higher cost.
The solar led light used in this video was purchased from Poundland and cost £2 for 3 lights or 67p each. Almost all of the cheap solar lights available can also be used for this purpose, just pick the units with the largest solar panel and if you can open one up the largest rechargeable battery. The electrolytic capacitor was removed from an old circuit board, Although it is preferable it is not essential, as the capacitance from the two wires running in parallel is usually enough to allow the circuit to operate.