1/2 AA and 14250 Batteries Equivalents and Replacements
1/2 AA and 14250 batteries are lithium cylindrical batteries commonly used in dog collars, security, and medical applications, wearable electronics, some EDC LED flashlights, computer motherboard batteries, etc.
There are several lithium battery chemistries, including both rechargeable and non-rechargeable types, used in 1/2 AA and 14250 batteries, which may lead to confusion among users.
Published: March 15, 2023.
1/2 AA and 14250 Batteries Features and Specifications
1/2 AA and 14250 batteries are cylindrical batteries with physical dimensions of (D x H) 14 x 25 mm (~0.5512 x 0.9843 inches), which is approximately half the height of very popular and widely used AA batteries (14.5 × 50.5 mm).
There are three basic lithium chemistries used in 1/2 AA and 14250 batteries, including:
- Lithium Manganese Dioxide (LiMnO2): non-rechargeable batteries with a nominal voltage of 3.0 volts and capacity in the 800-1000 mAh range. The most common labels are 1/2 AA 3.0V, CR14250, and similar. The most common 14 x 25 mm cylindrical battery is the "CR14250 battery", based on Lithium Manganese Dioxide chemistry.
- Lithium-Thionyl Chloride (Li-SOCl2): non-rechargeable batteries with a nominal voltage of 3.6 volts and capacity of around 1200 mAh. The most common labels are 1/2 AA 3.6V, ER14250, and similar. These batteries also feature a very stable output voltage, high-discharge cells support relatively large discharge currents and feature low self-discharge rates, while low-discharge cells feature a very low self-discharge rate (<1% annually).
Also, Lithium-Thionyl Chloride (Li-SOCl2) batteries feature excellent capacity considering the size of the battery.
- Lithium-Ion: rechargeable batteries with a nominal voltage of 3.6-3.7 volts and capacity of ~300-500 mAh. The most common labels are "rechargeable 1/2 AA", 14250, and similar.
Rechargeable Lithium-Ion 14250 batteries are often used in devices that are used daily. Although they feature a capacity of "only" 200-300 mAh, most models support up to 500 (or even more) charging/discharging cycles, saving, in the end, both time and money.
When charging 14250 batteries, dedicated lithium-ion battery chargers must be used - they charge lithium batteries with a Constant Current/Constant Voltage (CC/CV) charging algorithm and protect the batteries from overcharging.
However, when compared with Lithium Manganese Dioxide and especially Lithium-Thionyl Chloride batteries, rechargeable Lithium-Ion 14250 batteries feature lower capacity and higher self-discharge rate.
Long Story Short: If You are looking for a lithium cylindrical 14.0 x 25.0 mm battery, you are probably looking for a Lithium-Thionyl Chloride (Li-SOCl2) 3.6 volts non-rechargeable battery. These batteries have a high capacity, and a very low-self discharge rate, and can be used years after being stored away.
But, Lithium-Thionyl Chloride (Li-SOCl2) batteries cannot and should not be charged. Also, don't use low-current cells in high-drain applications due to the higher internal resistance.
If you are looking for a rechargeable 14250 battery, go for a Lithium-Ion battery that features a nominal capacity of at least 300 mAh and charge it using a dedicated lithium battery charger.