How much more life do you get with a Joy-Con battery pack?

I was surprised when I learned that Nintendo itself doesn't know how long the official Joy-Con battery pack lasts. So, I dove into YouTube videos, forums, and product reviews looking for answers from the wise people of the internet. But alas, there were no answers to be found. I was going to have to figure out the battery life of a Joy-Con battery pack on my own. So here's how I did it. Stick with me here, this is going to get a bit technical.

First off, I learned that a Joy-Con's internal battery lasts roughly 20 hours and contains 1.9 watt hours. Knowing that a battery pack runs on 2 AA batteries, I went to Duracell's website and learned that the average AA battery contains 1.5 volts. So a battery pack containing two AAs holds 3 volts total. I also learned that different types of AA batteries have different milliamp hours (mAh). The more mAh a battery has, the longer it lasts. AA batteries have between 1700 mAh and 2850 mAh depending on their quality.

If we assume you use a pair of Energizer's rechargable 2000 mAh AA batteries, you'd multiply 3 volts by 2000 mAh and that gives you 6 watt hours. Now, add that to the 1.9 watt hours of a Joy-Con's internal battery and you get 7.9 watt hours total. That's nearly four times as much as a Joy-Con on its own.

Since a Joy-Con lasts roughly 20 hours, you'll ideally get between 70 to 80 hours of gaming when using these Energizer batteries in a Joy-Con battery pack. If you use a pair of AA batteries that each have 2850 mAh, the battery pack could last you up to 100 hours. Keep in mind, there are many factors that will determine just how many hours the battery packs will actually last for.

According to Energizer, the optimal temperature for AA batteries is between 64 degrees and 131 degrees Fahrenheit. That being said, within this range, colder batteries last longer than room temperature batteries or warm batteries. I couldn't find anything that either verified or disproved this, but it's also possible that the batteries drain more as you press more Joy-Con buttons. This means more button intensive games might drain your battery packs faster. Most electronic devices use a lot of power when turning on and off. So the amount of times you power the Switch on and off will also affect battery life.

• Heat drains batteries so keep your Switch and Joy-Cons in a cool location
• Use AA batteries that have higher mAh
• Use fresh batteries or freshly recharged batteries
• Pay more for high-quality, long-lasting AAs
• Don't allow your Switch screen to completely run out of power

It really depends on how you play. Joy-Con's run for up to 20 hours on their own, which is more than enough time for most gaming sessions. This is especially true if you're charging your Switch between uses. But if you accidentally forget to recharge your Joy-Cons after a few days of playing, or if you'll be traveling with your Switch, then having a Joy-Con battery pack or a Joy-Con charger of some kind would be useful.