12 volt battery sizes differ because they are used in different applications and processes. Some are very light and others are heavy. Some look like typical AA batteries but others come in different shapes.
There are different specifications. One 12v battery may measure 8 3/16 x 6 13/16 x 8 3/4 inches, while others are 9 1/2 x 6 7/8 x 8 5/16, 9 x 7/16 x 5 1/2 x 8 15/16 or 10 1/4 x 6 13/16 x 8 7/8. There are also versions that measure 10 1/4 x 6 13/16 x 9 3/8, 10 1/4 x 6 13/16 x 9 3/4, 9 1/16 x 6 7/8 x 8 7/8 and 8 3/16 x 6 13/16 x 7 3/4.
Of course these figures are only applicable for those batteries made for cars. Those made for other electronic applications will have different 12 volt battery sizes.
Aside from cars, these batteries can also be used on boats and other vehicles. Some of these units are rechargeable. This is possible because only currents are required to get a vehicle going. Once that is done, the alternator gets the electrical system running. The alternator is also responsible for adding a charge to the battery.
The dimensions of these batteries differ according to the amp hours they are made to generate. Those batteries made for cars are heavier than other applications. But if the batteries are for children’s toy cars, the dimensions will be smaller.
Rechargeable batteries are utilized in different applications for outdoors. Others are non-rechargeable. If you end up using a lot of batteries, you are better off buying a rechargeable battery. There are also manufacturers who have come up with smaller versions. For example, some of these units can be used for fish finders.
Electrical on-board systems on boats can run fish finders. But if you don’t have one of these systems, the battery-operated ones will be sufficient.
Comparison with 6 Volt Batteries
A 12v has half a dozen battery cells while the 6v has only three. It means the 12v has more voltage. The amp hour capacity of a 12v battery is 200 or 2400 watt hours. By contrast, a 6v has an amp hour of 100.
Due to their diversity, 12 volt battery sizes ranges are extremely varied. But among the biggest measure 20 inches in length, 11 inches in width and 10 inches in height, while the smallest is 8 inches in length, 7 inches in width and 9 inches in height.