Designed for harsh environments, the Battery Tender 022-0258 battery charger & maintainer is weather resistant and built to endure elements. Perfect for industrial heavy duty machinery. Selectable chemistry allows you to choose between charging AGM, flooded, gel, or lithium (LiFePO4) batteries. Switch easily from 12V (5A) and 24V (2.5A) charging. The integrated mounting options lets you easily install on your vehicles and equipment.
I use two of these to keep my ex-military M151A2 Mutt batteries fully charged.