Golf carts use deep cycle batteries and some marine applications - but they are very expensive batteries. If you know someone that can get some second hand snap them up - way better than car batteries which are designed for crank amperage during start up and then charge via the alternator. (I have 2 GIANT 12V 80Ah deep cycle batteries for a solar power storage application at home, which were expensive but in this application they have already paid themselves off. I have yet to purchase a astrophotographical set up yet - hopefully soon. In the meantime I will use the gear I have - and last night was clear in Melbourne for a change
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