However, some conditions must be met before the Joy-Cons will actually charge.
However, they will only charge if the Switch is attached toan AC adapter.
The answer is to buy a dedicated Joy-Con charging dock.
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you’ve got the option to charge it directly with a Switch wall adapter or USB-C charger.
it’s possible for you to also connect it to one of the USB ports on your Switch Dock.
There are also special charging docks that can accommodate both Joy-Cons and Pro Controllers at the same time.
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Related:This Joy-Con Replacement Makes the Switch More Comfortable in Handheld Mode
This officially-licensed charging stand fro HORI can charge up to four Joy-Cons while attached to the USB port on your Switch dock or another USB power source.
This official Nintendo Grip turns your Joy-Cons into a more traditional controller and charges your Joy-Cons using a built-in battery.
The FastSnail Charger lets you charge Joy-Cons and a Pro Controller at the same time
