HMCS Windsor's return to Halifax has been delayed due to a battery cell malfunction, a spokesman from Maritime Forces Atlantic said Friday.

On Monday, crew members discovered a battery cell on the submarine had started to spread discharge to another cell, Capt. Cameron Hillier said. The batteries help propel the vessel.

"It was quickly isolated and contained," Hillier said.

"There was no fire or anything like that. Essentially, the issue was identified and immediately isolated."

'Minor mechanical incident'

HMCS Windsor has had problems before. In January 2015, it returned to service after months of unscheduled repairs and maintenance, which came under budget to around $17.2 million. That wasn't long after a $209-million refit was further delayed by a faulty generator.

Hillier said the navy considers this latest issue a "minor mechanical incident at sea."

The crew is trained and patrols regularly for problems, he said.

"When it becomes real life like this, they're well prepared to handle it," Hillier said.

HMCS Windsor, the only submarine on the East Coast, has a history of mechanical problems. (Molly Segal/CBC)

Specialists en route from Halifax

The submarine has two batteries with a combined 240 cells and each battery has a lifespan of five to six-and-a-half years, he said. HMCS Windsor's batteries are around five years old.

They were to be replaced this fall, but that schedule may change after an investigation, Hillier said.

The submarine is docked at the naval station in Norfolk, Va., after arriving under its own power. The crew is waiting for a team of specialists, engineers and technicians to arrive from Halifax, Hillier said.

Its 60 crew members were participating in an exercise with the United States Navy off the eastern seaboard. For security reasons, Hillier did not say when the sub is expected back in Halifax.

The submarine also participated in NATO exercises last fall before returning to Halifax in December.