Group Size Guide for Marine Batteries

Group Size Guide for Marine Batteries

In this week‘s blog, we will be outlining the replacement of batteries in your boat. When choosing brand-new batteries, however, the primary step is to size your battery bank according to your requirements. Typically, to get the exact same runtime as a wet or AGM lead-acid battery, utilize a lithium battery that is 60% of the capacity of the lead-acid battery you are changing.

BCI Battery Group Sizes

We‘ll start with a history lesson on what Battery Council International (BCI) is and what BCI group sizes involve. BCI is a non-profit trade association that was established in the 1920s to promote the interests of the lead-acid battery industry. Through the years, BCI has established technical requirements that consist of size groups for normal battery applications. To make them true drop-in replacements, we have sized our lithium batteries according to basic lead-acid group sizes.

The BCI group size range is rather broad, including cars, electric vehicles, and commercial batteries. The sizes of batteries that are normally used in marine applications fall into Group 31, Group 27, Group 24, and 8D. BCI established group sizes to make a normal standard for the maximum overall battery dimensions. Due to the fact that device producers try to reduce battery storage area, these group sizes define typical battery dimensions. Normally, a larger group size means that the overall capacity and dimensions of the battery will be larger.

Types of Marine Batteries

Marine batteries come in 3 primary types that consist of deep cycle, starting, and dual-purpose. Deep cycle batteries are used to power home loads that frequently consist of navigation aids, fish finders, running lights, radios, and trolling motors. On the other hand, starting batteries provide a short high current burst to get an engine running. Finally, there are dual-purpose batteries that are for both deep cycle and cranking purposes.

Typical Configurations of Marine Batteries for Trolling

Marine electrical systems are usually set up in 36, 24, or 12 volts depending on the dimensions of the watercraft and its trolling motor. If you have measured your power needs, you can obtain the voltage and capacity your system requires. If you have a 12-Volt trolling motor, you can select from the 12V alternatives that will satisfy your capacity requirements.

If you have a 24-Volt motor, you can use 2 12-Volt batteries in series with a multi-bank battery charger or numerous 24-Volt batteries in parallel to fulfill your capacity requirements. If you have a 36-Volt motor you can use 3 12-Volt batteries in series with a multi-bank charger.

Please contact us for more info if you require help determining appropriate replacement batteries for your boat or have any other issues.