The Food & Drug Administration slapped Medtronic Inc. (NYSE:MDT) subsidiary Physio-Control Inc. with a Class I recall of its LifePak 20/20e defibrillators, after the company declared a “field correction” for a battery problem last week.

Class I recalls mean the federal watchdog agency believes a product could cause serious injury or death.

The recall is the latest problem for the troubled Redmond, Wash.-based division of the world’s largest medical device maker. Physio-Control issued a “field correction” July 2, after discovering that some of the devices might lose battery power while in operation.

The device’s primary power source is wall power, but in cases where the battery fails and no wall outlets are available, the problem “could delay the delivery of defibrillation therapy, which could potentially result in serious injury or death” in devices manufactured before Jan. 9, 2009. Physio-Control said there have been reports of failures during patient use over the eight years the product’s been on the market and one, unconfirmed, “adverse patient event.” The company is notifying all affected customers by certified mail and plans to offer free updates with on-site field service visits. To figure out if a LifePak 20/20e is defective, customers can visit www.physio-control-notices.com/LP20Power.

In April, just a few months after the Food & Drug Administration cleared Physio-Control to resume defibrillator sales, the FDA issued a Class I recall of the LifePak 15 product. And last September, the FDA made the pull-back of its LifePak CR defibrillator a Class I recall.