Sonic Defender
Headphoneus Supremus
I got a response from Bowers and Wilkins about their battery.
Here's the response:
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Thank you for your email regarding the Bowers & Wilkins P7 Wireless.
The P7 Wireless Headphones are designed to last 300 full charge cycles. If there was a problem with the battery within the 2-year warranty we could replace them for you!
Kind regards,
Joseph H.
I would be most interested in knowing if it was even possible to change the battery. I suspect it would be possible, but require some technical skill and basic service equipment.