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Lead acid batteries are the most common type of deep cycle battery. They have been in use for a long time and are well understood. They have seen minor efficiency improvements over the years, though their efficiency and energy storage capacity both drop as they age.
Of all the off-grid energy energy storage media available, lead acid batteries offer the most bang for the buck (Watt-hour capacity per dollar spent) over the short term. (Lithium ion solar batteries are more cost-effective over longer time spans.) Because of their ubiquity, lead acid batteries are extremely common, and most of the renewable energy equipment on the market is designed to work within their voltage range. And they're 100% recyclable.
Lead acid batteries need regular use, maintenance, and ventilation to thrive. This means they're a much better choice for full-time off-grid homesteads than for vacation homes or emergency backup power. They also need to be protected from the elements. Over time, direct sunlight damages their housing, heat shortens their life, low temperatures reduce their effective capacity, and freezing damages their plates.
For best results, keep your lead acid batteries cool and dry, check their water level often, and deal with any corrosion at first notice.