Is your office cold? These power banks double as hard warmers – on purpose

One of the tests I do on power banks is a heat stress test. I charge and discharge as aggressively as possible, both with and without blanket insulation. It simulates a power bank that you carry in your pocket or bag and carefully monitors the temperature it reaches.

If it gets too hot it will be eliminated. According to , my right eyebrow starts to rise at about 45°C/113°F. ASTM C1055 According to the Standard Guide to Surface Conditions in Heating Systems Causing Contact Burns, the average person can touch objects up to 60°C/140°F for up to 5 seconds without sustaining irreversible burns. .

But this winter I’ve been testing power banks that are designed to get hot because they also double as hand warmers.

Yes, you read that right: a power bank that warms your hands.

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Before we go any further, let me let you in on a secret. Over the past few months, I’ve tested over 20 handwarmer power banks, but none were good enough to publish a review. Some were dead on arrival, others were running for an unusually short time, and some were dangerously hot.

But in the end, I found two power banks that passed the test. Both were from companies with a proven track record of producing fire, flame, and heat.

Zippo, best known for its flick-top lighters, has several power banks that keep your hands warm. heat bank 6 and heat bank 9s plus.

Technical specifications

Both power banks are small candy bar sized units with a very simple user interface. Both feature 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. Shows whether it’s on, battery level, and heat level (Heatbank 9s Plus has a small LCD, while Heatbank 6 uses a series of small LED lights). The Heatbank 9s Plus also has an LED flashlight feature.

There are slight differences in specs, with the Heatbank 9s Plus having a 5,200 mAh battery and 6 heat settings (3 settings and the ability to heat one or both sides), and the smaller Heatbank 6 having a smaller 4,400 mAh battery and 3 Two heat settings (the whole power bank gets hot).

And they work really well. The heat can range from subtle to obvious, but never reaches a level where it feels overwhelming or intense. To maximize battery life, we recommend starting at the lowest setting and working your way up. Because sometimes a little bit of heat can help relieve the chill.

If you want to keep your core warm, add a neck strap and wear it under your coat. A good way to really warm up on a cold day.

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As power banks go, both heat banks are a bit underwhelming. You can charge the latest and greatest devices with the right cable, but I think the USB-A output is for legacy devices. If you charge the power bank using the microUSB port, it will take over an hour to charge the small heat bank.

However, remember that 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 come across a better warmer.

There is one thing to note. It’s quite disconcerting when a power bank gets hot. There were a few moments where I was like, “Hmm…something feels off.” And the fact that Heatbank 6 is very similar to a regular power bank.

However, after extensive testing and the fact that the product was independently tested, UL solution — We are confident in the safety of this warmer.

ZDNET purchase advice

Both ZIPPO heat bank 6 and heat bank 9s plus Prices are reasonable, with the Heatbank 6 costing about $35 and the larger Heatbank 9s Plus about $60. Given the choice, I would choose the larger and more versatile Heatbank 9. Mainly because I like the fact that I can choose to heat one side and get through the day at a lower temperature. That said, both are great and come in a variety of colors that go well together.