Batteries of all types are found in every household.  If 12v batteries are what you're in the
market for then be glad you are reading this. 
The most common use for a 12v battery would be for a power tool. Which power tool you ask? Well the list is long but some of the brands
out there are:  Milwaukee, Craftsman,
Palsode, Panasonic,  Hitachi. 
Along with the many tool brands is the type of battery you
need. After you determine your brand, voltage and style matter also. When I say style, I mean specifically do you need a stick battery or a pod battery.  Let's look at the physical differences:
Pod Style 
Stick Style
Both aftermarket 12v batteries are an excellent choice for
whichever device you happen to own.  For
12v batteries in particular, not only do you have to choose your battery style,
but you also need to determine what battery chemistry type your device
requires. Not all devices require the
same thing.  Let me briefly explain.  Battery chemistry consists of Nickel-
cadmium, Nickel-metal-hydride, Lead-Acid, Lithium-ion, Lithium-ion polymer or
Reusable Alkaline. Before you purchase
any battery confirm the chemistry type. No need to waste your time and money ordering the incorrect battery. 
Let's not forget that a higher capacity battery will be
more advantageous when getting projects done therefore lessening the amount of
charges between jobs.  Whatever your 12v
battery need, Batteryship.com can help.