There are a number of variables requiring decisions when buying batteries.

Chemistry

The majority of existing installations use 12v lead/acid batteries. Aware that there is still some resistance to lithium LifePo4 (that we much prefer), we continue to offer them to those that refuse the change to lithium. Fire risk with LifePo4 is not an issue, and the batteries are lighter, charge faster, last 3 times longer, and are much more tolerant of repeated deep discharge. They are still more expensive, but we are satisfied that the extra cost is well worth it. Some engine alternators are not compatible with lithium batteries and can overheat or worse. We recommend the Sterling power alternator regulator on sale in the Products – Battery section.

Voltage

The standard remains 12v and for everything that floats there are items that are only available in 12v. Anchor winches, water pumps, and navigation lights are all 12v only. However appliances are uncommon and cabling needs to be much heavier so if other things are equal, it is best to minimise use of 12v. Hybrid inverters for 12v batteries are limited to 1500w output.

There is no significant advantage that we understand in going for 24v. However there are some 48v appliances, and, above all, more powerful 3 and 5w hybrid inverters need to be connected to 48v batteries

Formate

Regardless of the voltage, batteries with a capacity of up to 2400w are of the conventional format. Over that, vertical or horizontal power walls come into their own. Units range in capacity from 5 to 15Kw, and they are all 48v (51.2v) so combine perfectly with powerful hybrid inverters. They are heavy (50Kgs for 5Kw) but less bulky than the same power from conventional shaped batteries, and better value. Depending on your storage needs, they are the ideal solution.

Connection type – batteries and solar panels

The standard remains 12v and for everything that floats there are items that are only available in 12v. Anchor winches, water pumps, and navigation lights are all 12v only. However appliances are uncommon and cabling needs to be much heavier so if other things are equal, it is best to minimise use of 12v. Hybrid inverters for 12v batteries are limited to 1500w output.

There is no significant advantage that we understand in going for 24v. However there are some 48v appliances, and, above all, more powerful 3 and 5w hybrid inverters need to be connected to 48v batteries

We strongly advise against connecting more than 4 batteries together.