General Battery Terms and Information
Learn basic battery terminology to feel confident about your next battery purchase.
Common Battery Types
AGM: Absorbed Glass Mat refers to the separator material in certain VRLA/SLA batteries. The separator material is non-woven and made of glass microfibers that absorb and hold electrolyte, meaning none is spilled. These batteries require no maintenance and are often used in start-stop applications, such as your car.
Alkaline: Alkaline batteries are typical disposable batteries used in household items like television remotes and flashlights and battery-powered toys like RC cars. These batteries use zinc and magnesium oxide for the electrodes and an alkaline electrolyte of either potassium or sodium hydroxide.
Button Cell: Button cell batteries are disposable batteries used in small electronics like wristwatches. These batteries often have a longer lifespan than other disposable batteries. Some rechargeable button cell batteries are available.
Coin Cell: Coin cell batteries are similar to button cell batteries. They’re disposable and often used in small, portable electronics. They’re larger than button cell batteries and resemble the size of a small coin.
Deep Cycle - Marine: Deep cycle batteries, also called trolling batteries, supply a boat with continuous power. These batteries don’t deliver a burst of power to start the boat, but they give power to keep the boat running steadily and perform electronic operations like GPS and radio. Deep cycle batteries can be drained and recharged multiple times when cared for properly.
Gel: Gel cell batteries are another type of SLA/VRLA battery. In a gel cell battery, the electrolyte is mixed with silica powder to create a gel that immobilizes the electrolyte. These batteries are best for deep cycle operations as the gel can be quickly burned by too much power.
Industrial: Industrial batteries are designed for use in demanding environments where resistance to wear is required. While often used to power electric vehicles like forklifts, these batteries can also be found in remote areas where access to power is limited.
Lithium: Lithium-ion batteries are rechargeable batteries often used in mobile devices like cell phones, tablets, and laptops. In this type of battery, lithium ions travel from the negative electrode through the electrolyte to the positive electrode. When this type of battery is charged, the ions travel in reverse.
Ni-Cd: Nickel-cadmium batteries are used for small electronics and some toys. They’re rechargeable batteries that use nickel oxide hydroxide and metallic cadmium as their electrodes.
NiMH: Nickel-metal hydride batteries are similar to Ni-Cd batteries. However, they offer higher capacity than Ni-Cd batteries and use a metal hydride in place of metallic cadmium. These batteries are rechargeable and can be used instead of disposable alkaline batteries in many household electronics.
Rechargeable: Rechargeable batteries can have their charge dispelled and refilled many times. Popular rechargeable batteries include lithium-ion batteries found in most smartphones, but many batteries for cars, boats, and other vehicles, as well as some household electronics batteries, can be recharged and used over and over.
Sealed Lead Acid (SLA) / VRLA: Sealed lead acid batteries, also called valve-regulated lead acid (VRLA) batteries, operate using a valve system that prevents air from entering the battery to maintain the correct pressure for oxygen recombination. These batteries also don’t contain any free electrolyte. The electrolyte is immobilized by a gel or absorbed glass mat (AGM), reducing water loss and making these batteries relatively maintenance-free. AGM and gel cell batteries are two types of SLA batteries.
Silver Oxide: These batteries are often sold as button cell batteries and use silver oxide for the cathode material and zinc for the anode.
Specialty Batteries: These batteries are often small batteries designed to have a long lifespan, such as those used in watches and hearing aids. Coin and button cell batteries are types of specialty batteries.
Wet Cell: Wet cell batteries, also called flooded batteries, use a liquid electrolyte. The electrolyte level must be correctly maintained for optimal battery performance. These batteries are rechargeable and often used for power storage and backup power needs.