Amazon is recalling 260,000 AmazonBasics portable chargers after reports that they can overheat and cause fires or burns.
The US Consumer Product Safety Commission said Amazon received 53 reports of the chargers overheating, including one of a customer who was burned by battery acid.
There were also four reports of property damage due to fire and smoke.
The CPSC said customers should stop using the chargers and contact Amazon for a refund.
Seattle-based Amazon said it is also contacting customers.
The power banks, used to charge smartphones and other gadgets on the go, were sold at Amazon.com, Amazon book stores and Amazon pop-up shops between December 2014 and July 2017. They cost between 9 and 40 dollars (£6.45 and £28.60).
Amazon says customers can request a refund through its website, amazonpowerbank.expertinquiry.com .