Is your office cold? These power banks also serve as tough heaters, by the way

One of the tests I subject powerbanks to is a thermal stress test. I load and unload as aggressively as possible, both with and without a blanket to insulate them. This simulates the power bank being carried in a pocket or bag, and I closely monitor the temperature they reach.

If they get too hot, they are removed. My right eyebrow starts to rise at about 45°C/113°F, even though according to ASTM C1055 (the Standard Guide for Heated System Surface Conditions That Cause Contact Burn Injuries), the average person can touch objects up to 60°C/140°F for up to five seconds without suffering irreversible burns.

But this winter, I’ve been testing power banks that are designed to keep warm because they double as hand warmers.

Yes, you read that right, power banks that warm your hands.

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Before we continue, let me tell you a secret. In the last few months, I’ve tested over two dozen power banks with hand warmers and none of them had what it takes to post a review on them. Some were dead on arrival, had an absurdly short run time, or ran dangerously hot.

But I finally found two power banks that passed the test, both from a company with a history of producing fire, flames, and heat.

Zippo, a company best known for its flip-top lighters, has a couple of power banks to warm your hands: Heat bench 6 and 9s Plus Heat Bank.

Technical specifications

Both power banks are small units, about the size of a chocolate bar, with a very minimalist user interface: both have a button to turn the unit on and off, a microUSB port for charging, a USB-A port for power output and a basic interface. to show whether it’s on, the battery level and the heat level (the Heatbank 9s Plus has a small LCD screen, while the Heatbank 6 uses a series of small LED lights). The Heatbank 9s Plus also has an LED flashlight function.

There are slight differences in specs, with the Heatbank 9s Plus having a 5,200mAh battery and six heat settings (three settings and the ability to heat one or both sides), while the smaller Heatbank 6 has a smaller battery. of 4400 mAh and three heat settings (the entire power bank heats up).

And they work very well. The heat ranges from subtle to obvious, but never reaches the point of feeling overwhelming or intense. For the best battery life, I would recommend starting with the lowest settings and working your way up, because sometimes just a little heat is enough to ease a chill.

And if you want to keep warm, add the neck cord and wear it under your coat. It’s a good way to really warm up on a cold day.

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As an energy bank, both Heatbanks are a bit disappointing. I find the USB-A output best suited for older devices, although you can charge the latest and greatest devices with the right cable. Recharging the power bank using the microUSB port means it takes over an hour to charge the smallest of Heatbanks.

But remember, this is a hand warmer first and a power bank second. There are much better power banks on the market, but I have yet to find a better hand warmer.

One thing to note: it is quite disconcerting to have a power bank that gets hot! I’ve had a few “ooooh… that feels bad” moments, and the fact that the Heatbank 6 looks a lot like a regular power bank.

But after extensive testing (and the fact that the product has been independently tested by UL Solutions — I trust the safety of these hand warmers.

ZDNET Buying Tips

Both the Zippo 6 Heat Bench and 9s Plus Heat Bank They’re reasonably priced, with the Heatbank 6 around $35 and the larger Heatbank 9s Plus around $60. If I had the choice, I’d go with the larger, more versatile Heatbank 9s, mainly because I like the fact that you can choose to heat one side and at low temperature, that gives you good run time during the day. That being said, they are both great and come in a variety of colors to match.