Two separate batteries, not one
The case has its own battery, independent from the small batteries inside each earbud. The advertised \”total playtime\” figure is the earbuds\’ per-charge life multiplied by how many extra full charges the case battery can provide.
Why the case charges the earbuds, not the reverse
Power only flows one direction, from case to earbuds, through the metal contacts when they\’re seated properly. This is why misaligned earbuds in the case sometimes show as \”not charging\” even though the case itself has power.
Why case battery seems to drain even when not \”in use\”
A case with earbuds docked continues actively topping up their small batteries, which draws down the case\’s own charge even while sitting in a bag or drawer — this is normal, not a fault.
Charging the case without the earbuds inside
This is a legitimate way to top up the case\’s own battery on its own schedule, useful if you want to charge overnight without leaving the earbuds docked and slowly draining the case the whole time.
What actually shortens case battery lifespan
Like other lithium batteries, routinely leaving the case at 0% or constantly on the charger at 100% for extended periods gradually reduces its total capacity faster than moderate, partial-charge habits.
Why your case sometimes shows a different charge than expected
Case battery indicators (LED colors or percentage on an app) reflect the case\’s own remaining charge, not the earbuds\’ individual level — a case reading low can still fully top off the earbuds if there\’s enough charge left for one more cycle, which is a common source of confusion.