Alkaline and Lithium-Ion Batteries Serve Different Roles, Engadget Explains

Engadget reported that alkaline cells are relatively inexpensive and widely available for gadgets that draw power slowly. Li-ion batteries store more energy for their size and deliver substantial power repeatedly, though they usually require a charging circuit specific to the battery pack. Engadget distinguished between disposable lithium AA batteries and Li-ion batteries: a disposable lithium AA is typically an alternative or a 1.5-volt replacement for an alkaline AA and should not be confused with Li-ion. Both contain lithium-based chemistry, but their use cases are entirely different, Engadget said.

The article advised matching the battery to the job. TV remotes, clocks, wireless mice and similar low-drain devices are usually best served by alkaline batteries, which cost less and remain viable for a long time even if a package sits untouched in a drawer for a few months. Alkaline cells are mostly single-use and require replacement. Li-ion is the popular choice for devices that need frequent recharging, including laptops, cordless power tools and digital cameras, because its high energy density allows more runtime in a compact and rechargeable battery.

Disposable lithium AA or AAA cells sit somewhere in the middle, according to Engadget. They cost more than alkaline batteries but are a better option for devices that consume alkaline batteries quickly. They are typically best for emergency equipment, outdoor gear or devices consistently exposed to severe hot or cold weather from minus 40 to 140 degrees Fahrenheit. Engadget cautioned that battery type should not always be considered an upgrade. If a device specifically calls for alkaline cells, a lithium alternative should be used only if the manufacturer says it is compatible. Alkaline batteries should not be forced into a lithium-ion battery pack, and disposable alkaline or lithium cells should not be charged. Doing so can cause overheating or potential fires.

For people who run through AA and AAA stockpiles in a few days, Engadget said rechargeable Ni-MH batteries such as Panasonic Eneloop are a much better alternative to repeatedly buying alkalines. They are not lithium-ion, but they come in AA and AAA sizes and work in most everyday devices made for 1.5-volt disposable cells, though users should check instructions because some products are particularly voltage-sensitive. Rechargeable Ni-MH batteries typically push 1.2 volts. Engadget said rechargeables are great for devices that require fresh batteries often; keeping a charged set on hand means simply switching them out when needed.

Disposal also differs. In most of the United States, alkalines can go in the trash, except in California, though local or county rules may encourage or require recycling, Engadget reported. Lithium-ion batteries and the devices containing them should never go into household garbage or a random recycling bin because damaged cells can start fires. They should be taken to a dedicated battery recycler or a participating retailer. Engadget also advised taping up exposed terminals and keeping the batteries separate before transport.