16340 Rechargeable Battery and Its Equivalents: The Complete Guide
16340 battery is a cylindrical rechargeable battery based on one of the lithium-ion chemistries, ensuring relatively high discharge currents, stable output voltage, low self-discharge rate, etc.
As such, the 16340 battery is often used in high-output flashlights, photo/video equipment, toys, tools, and similar. However, there are several other very popular battery sizes that can, more or less easily, fit the 16340 battery compartments, leading to potential issues.
Published: January 23, 2023.
16340 Battery Features and Specifications
16340 batteries feature nominal physical dimensions of (D x H) 16 x 34 mm (0.6299 x 1.3386 inches), with a nominal voltage of 3.6-3.7V and a nominal capacity of 500-1000 mAh.
The maximum charging voltage is 4.2V, while the maximum charging current is usually in the 0.25-0.5 Amps (~0.5C) range.
However, the maximum discharge current varies from ~2.5 Amps to 7-10 Amps (3-15C), depending on the exact battery chemistry.
The maximum supported number of charging/discharging cycles is 300-500 cycles, although some brands claim 1000+ full charging/discharging cycles, which is, unfortunately, just a marketing trick.
Note: number of charging/discharging cycles depends on the charging/discharging current, charging method, storage and usage temperature, typical Depth of Discharge percentage (DoD%), etc., and can vary greatly.
Actual capacity and maximum discharge current are often related - batteries with ultra-high capacity are optimized for relatively low-current discharges, while batteries with relatively low capacity are optimized for very high discharge applications.
However, it is very difficult to make lithium-ion 16340 batteries with a capacity greater than 1000 mAh, although some brands claim 2500+ mAh capacities for some of their models - fake advertising, IMHO.
Protected vs. Unprotected 16340 Batteries
16340 batteries are flat bottom/button top batteries based on lithium-ion chemistries.
As such, it is highly recommended that they have a built-in Battery Management System (BMS) that monitors the batteries' condition and protects the battery from unwanted events like over-charging, over-discharging, over-current, high/low temperatures, and similar, by shutting off the battery when needed.
However, such systems require a little bit of space, decreasing the battery's capacity.
Thus, many brands offer the following:
- unprotected 16340 batteries with physical dimensions of 16x34 mm,
- protected 16340 batteries with physical dimensions of 16-17x 35-36 mm.
Although protected 16340 batteries are highly recommended, before purchasing, check their actual dimensions, just in case.
How To Charge 16340 Batteries
16340 and other lithium-ion batteries MUST be recharged using dedicated lithium-ion battery chargers that usually support charging of various battery sizes and chemistries and can come in very handy in many situations.
However, if You need just a few rechargeable 16340 batteries, another option is to get 16340 batteries with USB charging ports.
Just plug one end of the charging cable into the battery (most commonly the micro-USB port) and another end in the USB charger and recharge the battery in a few hours.
Note: 16340 batteries are often delivered semi-charged for safety reasons.
Again, protected 16340 batteries, especially with USB charging ports, although labeled as 16340 batteries, are actually 17350 or RCR123A batteries.
16340 Battery vs. CR123A Battery
Main differences between the 16340 battery and the CR123A battery are chemistry and dimensions:
- 16340 battery: 16x34 mm, rechargeable 3.6-3.7V Lithium-ion chemistry,
- CR123A battery: 17x34.5 mm, non-rechargeable 3.0V Lithium Manganese Dioxide chemistry.
Due to very similar dimensions, the 16340 battery can fit the CR123A battery compartment, but due to the voltage differences, it should NOT be done unless explicitly allowed by the device's manufacturer.
However, some manufacturers offer rechargeable CR123A batteries, which are labeled as RCR123A or 17345 batteries and feature dimensions of 17x34.5 mm, with some models having height up to 36-37mm, which is very similar to protected 16340 batteries, if not THE SAME!
Thus, if You want to replace your aging 16340 battery, be sure to check its actual dimensions - if it is close to 17x35-36 mm, You can probably also use RCR123A or 17345 battery.
16340 Battery vs. 18350 Battery
Another very similar battery is a lithium-ion rechargeable 18350 battery, with physical dimensions of 18x35 mm. Although the 18350 battery features a diameter that is 2 mm (~0.0787 inches) larger, 16340 batteries can fit battery compartments intended for 18350 batteries, but the contacts can be somewhat loose.
On the other hand, the 18350 battery doesn't necessarily fit the 16340 battery compartment.
The recommended course of action is to always check the actual battery sizes and act accordingly.
16340 Battery vs. 18700 Battery
18700 battery features physical dimensions of 18x70 mm and is approximately 2x as long as a single 16340 battery. 18700 batteries are not very common batteries, but very often, devices powered by 18700 batteries, flashlights, for example, accept either one 18700 battery or two RCR123A batteries.
Thus, the 18700 battery in such devices can be replaced by a pair of 16340 batteries, just be aware of potentially loose contacts.
16340 Battery vs. 18650 Battery
Lithium-ion 18650 battery is one of the most popular cylindrical lithium-ion batteries featuring physical dimensions of 18x65 mm.
However, very often, 18650 batteries are slightly longer (up to 67-68mm), especially models with the built-in BMS (also known as "protected 18650"), making them physically very similar to 18700 batteries.
Many devices that are designed to be powered by 18650 batteries also accept RCR123A/17345 batteries - two RCR123A batteries for one 18650 battery.
Thus, in such devices 18650 battery can be replaced by a pair of 16340 batteries, but be aware of potentially loose contacts due to the smaller diameter of the 16340 batteries.
16340 Battery Frequently Asked Questions (FAQ)
Here are some of the most common Frequently Asked Questions (FAQ) about 16340 and similar lithium-ion batteries.
What is a 16340 battery?
16340 battery is a cylindrical, rechargeable 3.6-3.7V Lithium-Ion battery, with physical dimensions of 16x34mm, supporting 300-500 charging/discharging cycles, and featuring an average capacity of 500-1000 mAh.
Are 16340 batteries the same as CR123A? Are CR123A and 16340 interchangeable?
16340 and CR123A batteries differ in size (16x34 mm vs. 17x34.5 mm), chemistry (lithium-ion vs. Lithium Manganese Dioxide), voltage (3.6-3.7V vs. 3.0V), and other features.
RCR123A battery is a lithium-ion rechargeable CR123A battery with a nominal voltage of 3.6-3.7V.
If your device supports the use of RCR123A batteries, often labeled as 17345 batteries, yes, 16340 batteries can be used, with potential issues with contacts due to slightly smaller dimensions.
Thus, always check the actual battery dimensions.
What can I use instead of a 16340 battery?
RCR123A battery, often labeled as the 17345 battery, can be used instead of the 16340 battery.
The 18350 battery is also very similar, but also a little bit wider.
Are CR123A and 18650 batteries the same?
No, these are different batteries, but some devices allow one 18650 battery to be replaced by a pair of CR123A or RCR123A batteries.
A pair of 16340 batteries can be used instead of one 18650 battery (or a pair of RCR123A batteries), but the contacts may not be so firm and reliable.
Few Final Words
If You have a device that uses 16430 batteries, check their actual size and the size of the battery compartment. Also, check the documentation of the device and see what batteries are supported.
There is a great chance that your device also supports the use of RCR123A or 17345 batteries - 16430 batteries can be found at local hardware stores and online shops, but RCR123A/17345 batteries are simply much more common.
Either way, go for the batteries from reputable brands that already feature plenty of positive reviews.
