Charging blocks and power banks


Editor’s note — This is the second of a two-part series.

Last week we started discussing device charging by looking at some standards and the connectors used in current charging methods. This week we’ll discuss charging blocks/adapters and power banks.

As a reminder, this is my last column for two weeks. I’ll be back after the first of January.

The battery in your device is rated in milliamp-hours, abbreviated mAh, and is essentially the size of the “fuel tank” for your device. A higher number indicates a larger battery or fuel tank which means that your device can go longer before it needs to be recharged (see for more detail). To recharge it you have several options.

Some devices support wireless charging. You don’t plug it in but instead set it on a wireless charging pad (no, we didn’t discuss those last week). Pretty much any wireless charger will work with any device that supports wireless charging. Apple recently introduced MagSafe. To clear up any confusion, MagSafe isn’t a charging standard, but rather a series of magnets on the back of the phone case that will cause your phone to attach to a charger equipped with compatible magnets. The MagSafe part isn’t the charger, it’s the magnets. Pretty much any phone that supports wireless charging will work with any wireless charger. An article at does a good job of discussing MagSafe and how you can take advantage of the magnets on a phone that supports wireless charging but doesn’t have the MagSafe magnets.

Wireless charging is relatively inefficient in that some energy is lost to heat as well as some inherent loss due to how power is conveyed to your device. A more efficient way to recharge is just to plug it in. Charging stations can be really simple with one port which will let you charge one device to multi-port charging stations that support both Power Delivery and Quick Charge and they can plug into a wall outlet or into your cigarette lighter in your vehicle. Because of the way power works, charging stations and power adapters are rated in watts (abbreviated W).

If we continue the fuel tank analogy, watts can be thought of as being a measure of how quickly the “fuel” is loaded into the “fuel tank.” Your phone might support 18W or 25W fast charging, which means it will charge much faster than a standard phone. How much faster? Your phone’s manufacturer will tell you that. But your power station/charger must support passing energy to your phone at that rate. Power Delivery (PD) chargers quote the rates at which it can supply power. A PD charger, when paired with the right cable, can negotiate with your phone and cable to send as much power as your phone and cable can support, within the bounds of what the charger can provide. And, while all of this is interesting, a simple charger will charge your device quite well. Maybe not as fast, but certainly without all the hullabaloo and machinations you need to go through to figure out how to get the absolute fastest charging possible.

OK, so after all that you might ask what should I buy? Here’s a list of various types of wall chargers from The Wirecutter and here’s their list of car chargers

A power bank, being just a battery, has the same measure of capacity as your phone. If your phone has a 5,000mAh battery (which you can find on the box or from the vendor from whom you bought it) and your power bank is 20,000mAh it can recharge your totally dead phone about four times before the battery in the power bank is exhausted (I say “about” because some of those mAh are lost during the charge process).

Power banks follow the same standards we discussed last week. Some may have Quick Charge or Power Delivery, or both, or neither. Some have wireless charging and some even have a digital readout that tells you how much “fuel” is left in its “tank.” Like charging stations, if you want to get the absolute fastest charging from your power bank it needs to be matched to your cable’s and your phone’s capabilities. But if you just want it to recharge your device pretty much any power bank will do. Just make sure it’s from a reputable manufacturer or it has favorable reviews from a reputable source.

At some point you’ll need to recharge your power bank. It can take a long while to recharge a sizable one of, say, 10,000 or 20,000mAh. In addition to their output specifications which we have been discussing, power banks have input specifications and they tend to match the output specifications. In other words, if your power bank doesn’t support Quick Charge or Power Delivery to charge your devices, it will likely not support either of those to recharge the power bank so it could take three to five or more hours to recharge. While you may not need to charge your device quickly, you may want to more quickly recharge your power bank. Keep that in mind when making your purchase decisions.

I’ve reviewed a number of best lists but I couldn’t come up with two or three good, representative lists. Each publisher has its own criteria for their ratings so I’ll give you a couple of brand names that I have come to trust. I have a number of products from each of them and had good experiences. They are Anker and UGREEN. Certainly they are not the only ones that are good and reliable but they are two brands I like and I can get quickly from Amazon. By all means, do your own research and choose based on your own needs.

That’s charging and power! Let me know if you have any topics you’d like me to cover.

As always, my intent with these columns is to spark your curiosity, give you enough information to get started, and arm you with the necessary keywords (or buzzwords) so you’ll understand the basics and are equipped to search for more detailed information.

Please feel free to email me with questions, comments, suggestions, whatever at [email protected] or just drop me a quick note and say hi! And don’t forget that I maintain links to the original columns with live, clickable links to all the references at or Iit should be updated shortly after this column appears online.

Tony Sumrall, a Hillsboro native whose parents ran the former Highland Lanes bowling alley, is a maker with both leadership and technical skills. He’s been in the computing arena since his graduation from Miami University with a bachelor’s degree in systems analysis, working for and with companies ranging in size from five to hundreds of thousands of employees. He holds five patents and lives and thrives in Silicon Valley which feeds his love for all things tech.

No posts to display