Alkaline 12V A27 Battery

The alkaline A27 battery is a cylindrical 12V battery commonly used in remote controls for garage door openers, home security alarms, window security sensors, wireless doorbells, ceiling fans, LED flashlights, toys, some dog collars, laser tags, clocks, and similar devices that require relatively high, 12V voltage.

The alkaline A27 battery shares many similarities with a somewhat larger A23 battery, with some devices being able to use both of the batteries thanks to the plastic battery adapter for the smaller A27 battery.

Published: March 16, 2023.

A27 Battery Features and Specifications

The A27 battery is a cylindrical battery featuring physical dimensions of (D x H) 8.0 x 28.2 mm (~0.315 x 1.110 inches), a nominal voltage of 12 volts, a cutoff voltage of ~7.2 volts, and a nominal capacity in the 25-35 mAh range.

Note: Nominal capacity depends on the battery age, device cutoff voltage, drain current, temperature, etc.

Internally, the A27 battery features 8 (eight) button/coin-cell LR732 batteries stacked up and connected in series, providing the required voltage (12V) and capacity.

Individual LR732 batteries are not used, at least not very often. Still, if eight of them are stacked up, one gets a battery pack that is 7 mm wide and some 25.6 mm high - such a battery pack can't firmly fit into the battery compartment intended for an A27 battery (8.0 x 28.2 mm).

However, if required, eight LR41 or eight SR41 batteries may be stacked up to form 12.0 volts (LR41) or 12.4 volts (SR41) battery pack with physical dimensions of 7.9 x 28.8 mm, which is very similar to the A27 battery dimensions (8.0 x 28.2 mm).

Note: If You need an alkaline A27 battery, go for an A27 battery - a plain and simple solution. Stacking eight LR41/SR41 batteries is not recommended and is done only on your responsibility.

Cylindrical 8.0 x 28.2 mm battery features several labels, including A27, 27A, A27BP, G27A, GP27A, L828, L828F, MN27, V27GA, EL812, 8LR732, with the A27 battery being the most common one. Thus, should one ask for battery replacement, then:

• MN27 Battery Equivalent: A27 battery, 27A battery, L828F battery, etc.
• L828F Battery Equivalent: A27 battery, 27A battery, MN27 battery, etc.

A27 Batteries Comparison Chart

The following comparison chart lists several very popular A27 batteries, with their most important features and specifications:

Battery Datasheet	Capacity	Operating Temperature	Annual Self-Discharge Rate	Discharge Current
Duracell MN27	20 mAh, 20kΩ down to 6.0V @20°C	-10°C to +60°C	<10%	-
Energizer A27	27 mAh, 20kΩ down to 6.0V @21°C	-	-	0.5 mA over 20kΩ @21°C
GP Batteries A27	20 mAh, 20kΩ down to 6.0V @20°C	-	<5%	0.5 mA cont., 5 mA max. pulse

As one can see, A27 batteries are typical alkaline batteries with an average annual self-discharge rate of 5-10%, capacity in the 20-27 mAh range, a standard discharge current of 0.5mA, and max. pulse current of ~5 mA.

A27 Battery vs. A23 Battery

Both A27 and A23 batteries are alkaline 12V batteries internally, consisting of 8 alkaline button/coin cells stacked up in series.

They differ in size and hence the capacity:

• A27 battery: 8.0 x 28.2 mm, 8 (eight) LR732 cells connected in series, 25-35 mAh capacity. It can be replaced with 8 LR41/SR41 batteries, but NOT recommended.
• A23 battery: 10.3 x 28.5 mm, 8 (eight) LR932 cells connected in series, 50-60 mAh capacity. It can be replaced with 8 LR936/SR936 (LR45/SR45) batteries, but NOT recommended.

Some devices feature a small plastic battery adapter where an A27 battery is inserted, allowing a somewhat smaller A27 battery to fit firmly into the battery compartment intended for the A23 battery.

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Long Story Short: Alkaline A27 batteries are manufactured by the most popular battery brands and can be easily found at most hardware and office stores and online shops - there is really no need to replace them with individual button/coin cell batteries.

With their shelf life of 2-4 years, sometimes even more, A27 batteries are quite common in RF and other similar electronic devices.