Both McLaren (twice) and Red Bull were sidelined yesterday as a result of "electrics" issues that were eventually traced to the battery.

However, the works team's technical director, Bob Bell, has dismissed claims that there is an inherent issue, insisting that it was essentially the luck of the draw - that the offending batteries were from a bad batch - and that it was better the faults happened in testing than in Melbourne.

"The issues that we've had I don't think have any relationship to the installation of the battery at all," said Bell, according to the official F1 site.

"We haven't had any problem," he continued, referring to the works team, "but what we do ahead of Melbourne is that we try and shakedown all of the battery systems to make sure all of the stock that are going racing are in good shape.

"That's why we test them here. We revolve them around the customer teams and ourselves to make sure they are all tested ahead of Melbourne. So it's not unusual to find issues."

Insisting that both McLaren and Red Bull receive the same spec units as the works team, Bell believes yesterday's issues are a positive as it means the problematic units can be removed from the pool before Melbourne, a vital move considering this year's strict rules on power unit components.

"Those problems could have affected any of the three teams, so of course it's an issue for us but the reason we do this testing of those components before going to Melbourne is to find the ones that have got problems.

"It's the right thing to do," he added, "we have found some that are not fit for purpose and that's great.

"By regulation, each driver gets two units per year, so that's what they are designed to do. That's a pretty heavy duty cycle for them, and the importance of making sure they are completely fault-free is critical, which is why we test them ahead of Melbourne."