I have purchased an auxiliary 18 Ah lithium battery to supplement the stock 13 Ah battery. For convenience, I would prefer to configure them in parallel for operation. The resulting slower drain should extend battery life. But there will be many situations where the batteries will be separated and become dissimilar in charge. I want to do something to stop or slow excessive reverse current flow that could damage my batteries.
Are Schottky diodes right for the task and can anyone draw me a schematic or share any relevant advice?