Rechargeable Batteries
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Lithium-ion and AA
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long-lasting
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rechargeable
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no extra cables
I'll be honest - I love these. What a phenomenal invention. I've never been more passionately in love with a battery.
The battery itself has the port! You plug the wire into the battery! No battery recharge dock or specialized tools!
Some items will never upgrade to rechargeable lithium-ion batteries and some items use weirdly specific cables (e.g. every electric shaver). When traveling, it's important to cut down on extra items and stick to multi-use ones. I can stop worrying about "how much charge I have left" and just recharge these bad boys with a USB-C cable!
Note that for these specifically, I found I had to use the included cable over a regular one to get any charge, but it's compact enough that it's not really an issue.