What Are the Best Motorcycle Batteries for Your Bike?

The only time most people think about motorcycle batteries is when they are all set to go for a ride and their bike won't start. There is nothing more frustrating than hopping on your bike and realizing the battery doesn’t have enough power to get you going.
So, unless you ride with two Olympic bobsledders to help you push start or only park at the top of long hills, you need a good motorcycle battery to keep your bike starting reliably. How do you decide on the best battery for your bike? Well, that depends on several factors. At a bare minimum, you really need one that fits in your battery box properly so it doesn’t move around and damage itself or the connections. It is best if the battery is the same size as the original battery, although sometimes you can use a spacer to raise a shorter battery up to the same height as the original so the cables will be able to connect. Maybe you really need an inexpensive battery that will do the job, so price would be your number one concern. Or maybe you know your bike needs more power than the original battery had, so cranking power (CCA) would be your most important feature. Maybe you want to go racing and weight is your top priority.

Motorcycle Battery Technology

There are several types of batteries out there that address these considerations. Just like most cars these days, most motorcycle batteries are the good old lead-acid battery that has been around for well over 100 years.
There are alternating cells of lead and lead oxide that are submerged in a sulfuric acid electrolyte. When discharged, sulfur from the electrolyte deposits on the plates. Sometimes this is geekily called "sulfation", although I prefer the term "dead". Lead-acid batteries typically have caps over the cells so you can replace any evaporated electrolyte with add distilled water so the cells stay submerged. There is the potential for leakage, so you have to keep these batteries upright.

An AGM (Absorbed Glass Mat) battery is a sub-type of this long-standing technology. Though still technically a "wet" cell, the AGM type uses a fiberglass mat to contain the electrolyte and hold it permanently against the cells. This is a type of sealed battery, so you don’t have to worry about spilling the acid if the battery is laid on its side or turned upside down.

Another type of sealed battery is a gel battery. As its name suggests, the electrolyte is a gel and it stays in contact with the plates at all times no matter the orientation. Both of these maintenance-free motorcycle batteries are more expensive than the traditional lead-acid battery. They are said to offer increased life, so that's a plus.

Newer developments include LiFEPO4 (Lithium ferrous sulfate) batteries. I've never used one, but they claim to have quicker recovery from voltage draws on multiple start attempts than traditional styles. They are much smaller than traditional types for equivalent power and therefore much lighter as well. This type of battery is said to be better for the environment since it contains no lead or acid. They are true dry cells, so once again, installation direction is not important. Price is higher yet than either the AGM or gel batteries since this is a newer technology and is marketed as a high-performance product.