About 6 years ago we purchased the first of three Pelican re-chargeable torches. They're waterproof, lightweight, robust, very bright and have a lifetime guarantee. Best of all, the model we chose comes with a small 12volt re-charging cradle, which we installed at the Nav. station and wired into the switchboard supply. So the torch was always fully charged when we needed it.
After several years of service we experienced a few charging problems, and one torch stopped working after its first salt water immersion. So we sent all three units back to the manufacturer. To our delight they agreed to replace all three units at no charge - and they let us upgrade to the new LED versions for a small fee. Full points to Pelican for honouring the lifetime warranty without any questions - service like that is hard to find these days.
We use the Pelican Stealthlite 2460 Recoil LED ( see the manual here ). Its waterproof, though they say its not a diver's light - they have other models for that. Our thanks to Pelican Australia for the prompt service and great support.