How to Keep the Life in Your Batteries

One of the biggest issues of an electronic lifestyle is how make sure you have enough power for all your gadgets. Electronic devices eat power like there is no tomorrow, which is why so many people have been switching to rechargeable from disposable batteries.

What about Battery Technology?

While most disposable batteries rely on alkaline technology, there are two main forms of rechargeable battery technology; lithium-based and nickel based. Each offers a different set of benefits and challenges:

  • Nickel: Initially used in NiCd, and later NiMH batteries, nickel technology is the most common chemistry in AA rechargeable batteries. While these batteries are drop in replacements for disposables, they do produce a slightly lower output: 1.2 Volts instead of 1.5. Luckily, this is not usually an issue as alkaline cells generally lose voltage over time and average out to the same 1.2 V as NiMH. The other issue these batteries have is that they are also subject to voltage depletion, which can limit the amount of charge they can hold. 
  • Lithium: Most commonly appearing in Li-ion batteries, lithium-based cells provide power for a wide range of devices and has rapidly become a favored rechargeable battery technology for most uses. However, they default to 3.7 Volts, which is too high for a drop-in AA battery replacement, so they do not appear in every form of battery.

What About Lithium AA Batteries?

Luckily for those looking for the benefits of lithium batteries in the convenience of the AA form factor, companies like KENTLI have developed Li-based rechargeable batteries that do fit in an AA case and offer a 1.5 Volt output.

  • Lithium-Ion AA Batteries: KENTLI AA batteries base around a polymer, but the principle is the same. What makes the AA format LiPo battery possible is the presence of a voltage regulator that drops the current output to 1.5 Volts so that it does not damage your equipment.
  • Lithium-Ion Chargers: Lithium-ion batteries require special chargers to work, as it's very important that the charger contain circuitry to prevent overcharge and the attendant risks of fire. The AA charger also requires a second electrode, so it can recharge at the 3.7 Volts the charger calls for.

Battery Usage

Applications like remote controls do better with disposable batteries, with their long shelf life and low self-discharge characteristics. Rechargeable cells are better for higher current applications where capacity matters more than storage. This is the battery you want to put in a camera or other device that uses more power over a shorter period of time. The advent of the AA format lithium battery is another step forward in portable electronics.