Keep your Quest 3 fully charged while playing, might work on the Quest 2 as well

The issue is so simple that most people won't consider it as a cause 😉
The supplied charger is NOT PD rated, is NOT rated for fast charging.
As least not based on the USB specifications.
The supplied cable is NOT rated for fast charge, is NOT rated for PD use.
So if you take you fancy fast or PD charger nothing much will change.
Especially not if the charger has a standard USB port where it MUST have a USB C port that is fully equipped 😉
Now, let's assume you got a properly rated cable and a proper 45W or more USB C charger....
With that combo you CAN charge from near empty to full in under 2 hours.
What (in most cases) you still can't do is to CHARGE while playing hard.

The headset will request various Voltages and charging rates.
In order for this to work the cable has to be a match to the USB specifications.
The charger has to be able to provide what the headset requests as otherwise it will revert to the default charging rates - which are significantly lower.
Biggest problem however is that most USB C CHARGERS with a PD rating are not able to do both at the same time.
Means they can either charge OR provide power (at a high rate) but not both.

Oh:
If you are the cautious type and use these nifty MAGNETIC USB C charging/data cables.....
They won't work as the vital power and signal lines are missing.
And if you grab those under $15 and 3m long USB C cables you will that they won't work either.
You REALLY need a proper cable rated for fast charging and preferably also for PD.

None of my chargers keep the green light on while playing....
Assuming you have a proper cable it means you need a proper charger.
These above 45W models cost quite a few bucks if you want quality.
A far better alternative is a LAPTOP POWER BRICK of the USB C kind !

What's the difference ?
For a charger it is a game of luck unless you really know what to look for.
A laptop power brick HAS TO WORK for both charging and providing power, preferably fully independent.
Many laptop manufacturers now USB C for the charging thanks to the new laws in the EU.
Going for 65W model is enough, 100W is overkill.

Ok, sounds nice but what IS the difference and what are the bad things ?

With a laptop power brick the Quest (3) will use one channel to power the headset while the second channel is use to charge the battery.
Means this:
The battery is charged without the headset draining it at the same time.
All the power the headset needs to run comes directly from the power supply.
In return this mean no energy wasted, no energy turning into useless heat as a result.

The downsides are obvious:
If you use a power brick to fast charge the headset it will put additional strain on the battery, reducing the lifespan and capacity over time.
Thankfully Meta will discontinue the headset before any of this becomes an issue.

Charging while using the headset will result in a lower charge rate but since the battery is not used by the headset...
You can start watching a long movie with the battery almost drained.
With the laptop brick plugged in the battery might be full by the time the movie is over...

Biggest benefit is also the biggest downside.
With a power brick the Quest 3 won't have to throttle things down to prevent excessive drain on the battery.
This otherwise vital protection feature gone means it is only the heat management left to slow things down.
So if you switch to 120Hz, enable all the good graphics stuff in the game then things will get warm....
NOT as warm tough as using an unsuited charger / cable combination....

I use a 65w gan 3 pd charger and a 100w cable and have zero problems providing enough power to keep it charged indefinitely while playing 

I've had my quest 3 for 2days now and I'm not impressed, head band is crap, battery is useless only allows 2 hr play time. Wishing I hadn't purchased it. I play sim racing in a league that goes for 4 hrs. This headset just doesn't cut it.

Great insight on the Quest 3 battery situation! I've had similar issues, especially with longer play sessions or movie watching. Upgrading to the battery strap was a game changer in terms of comfort, but you're right, it doesn’t quite deliver the extra playtime you’d expect. I’ve also noticed that balancing the charge between the internal battery and the strap can be tricky. I tried the 45W charger, and while it does help a bit, I’ve found using a power bank alongside it has been the best solution for me to keep it running smoothly. Keeping everything cool is key, so I take breaks when I can. Still, loving the extra comfort and slightly longer battery life!