BU-810: What Everyone Should Know About Aftermarket Batteries

In the search for low-cost batteries, consumers may inadvertently purchase counterfeit batteries that are unsafe. The battery label appears bona fide and the buyer often cannot distinguish between an original and a forged product. Mobile phone manufacturers are concerned about these products flooding the market and advise customers to only use approved brands; defiance could void the warranty. Manufacturers do not object to third-party suppliers as long as the aftermarket batteries are well built, safe and approved by a safety agency.

Consumers are not the only buyers leaning towards aftermarket batteries. Public safety, healthcare and other organizations also take advantage of economically priced replacement batteries. Industrial aftermarket batteries are normally prequalified and many perform well, but the quality can be less consistent than the brand-name product, and some packs are said to be underperforming. Aftermarket batteries are mostly used for non-critical applications because liability issues could counter any savings gained.

Caution also applies when purchasing aftermarket chargers. Some low-end units may not terminate the battery correctly and rely on the battery’s internal protection circuit to terminate the charge when the battery is full. Redundancy in charging is important as the protection circuit of a bona fide battery can be damaged(See also BU-304b: Making Lithium-ion Safe)

Aftermarket batteries may also have insufficient safety provisions and rely on the charger to terminate the charge. Marrying the two aftermarket partners could turn battery charging into an unwanted event. Accidents are bound to happen when connecting a mobile phone or e-cigarette to the 12-volt system of a vehicle with a faulty inverter. Personal injury and damage can be the results.

Some manufacturers of laptops, medical devices, e-bikes and others disallow aftermarket batteries by digitally locking the pack with a tamper-proof security code. This is done in part for safety reasons; it also secures for the manufacturer a future demand for batteries with good margins.