I have a solar panel 14 watts and I want to connect it to two 110 Amps leisure batteries. I dont want to buy expensive controllers etc. I think that the only thing that I need is to put one or two diodes to ensure that the current does not flow back into the solar panel at nigh. I am correct ? If so, can I buy diodes from High Street stores like Maplin and what do I ask for?. How do I connect them? Many Thanks in advance.