In A Nutshell
- Kentli makes the best rechargeable lithium-ion AA batteries currently available. They are rated at 2800mWh, and are the only 1.5 V li-on AA batteries, making them the best choice for consumer-grade electronics.
- EXCELLENT makes 3.7V li-on batteries compatible with high drain devices like LED flashlights.
Not long ago, disposable alkaline batteries enjoyed an undisputed mastery of the AA battery market. Improvements in rechargeable battery technology upended that dominance over the past decade. As we reported in this article, Nickel-Metal Hydride (NiMH) AA batteries such as Panasonic’s Eneloop have made rechargeable options more cost-efficient in the past 10 years.
A 1.5V lithium ion battery has recently been made available to consumers. Lithium ion cells have a high energy density, long cycle life, and have a lower self discharge rate than NiMH batteries. In other words, they last longer and maintain a more even voltage than other types of cells.
Kenli’s 1.5V offering is an ideal choice for everyday household needs. The batteries have the same voltage as a brand-new alkaline battery and won’t overpower devices that just need a stock battery.
2800mWh is a respectable capacity, equivalent to around 1866mAh. By comparison, the Eneloop Pro has a capacity of 2550mAh. Like most NiMH batteries, the eneloop pro is 1.2V.
This equation explains the difference between mWh and mAh:
miliWatt x Hour = Volts x miliAmpere x Hour or mWh = V x mAh. For more on the conversion process, read here.
Higher voltage lithium-ion rechargeable batteries are made for high-performance flashlights and cameras, but they are not intended for use with many products. They are higher energy density and rated at 3.7V.
EXCELLENT is one company producing higher energy density lithium ion batteries. Their 18650 batteries have a 2600mAh capacity and high quality cells. They are 3.7V and great for UV or high powered LED flashlights that consume a lot of energy.
One word of warning too consumers: there is currently no standard size for these lithium-ion cells. Make sure to read the dimensions of each battery on Amazon before you buy to guarantee that they will fit in your device.