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Zendure USA Inc. was founded in 2013 by Tom Haflinger and Bryan Liu. Our mission is to deliver top-quality consumer electronics that exceed consumer expectations using high-end materials, premiere product development partners and user-centric design. Zendure’s first product was the A-Series External Battery, which was supported by over two thousand people during a one-month Kickstarter campaign, making it one of the most successful external batteries projects out there.

We strive to keep innovating, designing trustworthy products, and improving people’s lives. Take a look at how far we've come.

Watch our original Kickstarter video below.

We make our products with YOU in mind. Here are some features you will find in our A-Series power banks.


Most lithium-ion batteries are capable of being charged and discharged about 500 times. This is sort of the "life expectancy" of the internal components. The primary job of the exterior is to protect the internal components over the life of the product. Using the world’s most advanced industrial design and molding techniques, our engineering team was able to build an external battery that has unprecedented durability, inside and out.

Zendure A-Series batteries are made from a durable composite material (Polycarbonate +ABS) thats used in a vast array of other resilient products, including high-end suitcases, and the recent iPhone 5C. The exterior shell is reinforced by support ridges to resist warping. Between the front and back covers is a shock-resistant rubber belt (polycarbonate + TPU) to help protect the battery from drops.

During production of our Kickstarter video, Zendure founder Bryan Liu ran over a Zendure A4 battery a dozen times while charging an iPhone 4S, and the battery passed the test with flying colors.

While the car test certainly is flashy, numbers matter too. All three models were put through two hours of drop tests, falling repeatedly onto a hard cement surface from one meter. The three models also spent ten hours dancing around during a formal vibration test. Again, flying colors across the board. And the internal batteries have been vetted by their manufacturer after suffering several hours of impact tests by a 9kg hammer dropped from 60cm, as well as a ten-second encounter under a total weight of more than 1300kg.

Energy Efficiency

Current owners of external batteries may already be aware that a battery’s rated capacity is not a clear indication of actual performance. Internal resistance takes some of the energy out of the system. The batteries themselves usually hold a charge at about 3.7 volts, while the devices that they power require 5 volts. This transformation takes energy out of the system, as do other circuit operations.

For most batteries on the market, this energy loss reduces the effective capacity by up to 30% of the total power of an external battery. Their total energy conversion rate (TECR) is only 70%. Zendure A-Series batteries have an amazing 80% TECR. That means our milliamp-hour (mAh) charge ratings are worth more than the figures our competitors use. It also means that every gram of mass, every cubic centimeter of space taken by our batteries is used in the best way possible. Some manufacturers claim that their batteries’ conversion rate is 90%, but they are usually talking about the efficiency of the circuitry itself, not the TECR. Our circuit efficiency is 95%.

We achieve these results by employing a design that includes the best internal batteries, the best control chip and a passive cooling system that transfers heat away from the internal components. In addition, our batteries can go through over 500 full charge/discharge cycles over the life of the product.

Charge-Through Technology

Most batteries we encountered are not capable of charging other devices while they, themselves are being charged. Not surprisingly, our research indicated that most people would rather have a battery that can do both at the same time. In fact, a large number of consumers purchased an external battery under the assumption that it would be able to do this, only to find out later that their assumption was incorrect.

The Zendure A-Series can charge other devices while it is being charged. So you don’t have to constantly rearrange your charging cables or plug in two wall chargers. Just leave everything plugged in, and let the A-Series take care of business.

Auto Power-On

The Zendure A-Series will automatically turn itself on when connected to a compatible device for charging, then switch back to standby when charging is complete.

Long-Term Standby

If you’re planning to purchase a battery to use as a backup in your home emergency kit, you’d probably rather not have to "top off" the charge every couple of weeks so it will be ready when you need it. The Zendure A-Series battery can maintain up to 95% of its charge after six months without use, so it won’t let you down in an emergency.

Dual USB Output

Sharing is caring. Think of what a good friend you would be if you had an extra charging port for someone who needs it. Or charge two of your own devices at the same time. However you roll.


Zendure A-Series batteries are designed for compatibility with a variety of USB-powered devices, including smartphones, tablets, music players, cameras, e-readers and game consoles.

Our Story

The key to building a great product is to focus on the people who will be using it, so we started with consumer and market research. What do people look for when they’re deciding which battery to buy? What factors determine satisfaction with the product?

We began by looking at existing products on the market, getting an idea of how well they were selling, and finding out what people were saying about them after their purchase. We read over a thousand reviews on a variety of websites. Coffee helped.

We also bought batteries from a variety of manufacturers and tried them out for ourselves.

Then we put together some focus groups and interviews to really get in touch with our consumers. We brought in current battery owners and also mobile phone users who were considering shopping for one. We asked them how they decided which products to buy, or how they were planning to begin their search. We showed them existing products as well as some experimental mock-up images and got their opinions on aesthetic value. It was a really great experience. Our participants gave us detailed answers to our questions and were really supportive in our quest to figure out how to make the best possible battery.

We wanted to design something that looked rugged, but at the same time, luxurious. The design for the A-Series was inspired by high-tech machinery and also by existing products in other fields that we felt shared a similar design philosophy.

While founder Tom Haflinger conducted the interviews in the U.S., co-founder Bryan Liu started looking at potential manufacturers in China. We were looking for a facility with a lot of experience, a reputation for making quality products, and a high output volume. At the same time, we didn’t want some cold mega-corporation that would rarely return our emails.

Bryan found a great team in southern China with an incredible reputation. After meeting with the owner in person and touring the facility, we were convinced that these were the folks we wanted to work with.

After countless sketches, renderings and revisions, our final design was born.
Of course, developing a product that is actually as durable as it looks takes a lot of testing. The manufacturing facility had the necessary equipment and talent to put together the exterior shell and run it through their "torture chamber". Trial after trial indicated that we should use a strong polycarbonate-ABS blend that could keep up with a life in motion. The top and bottom shell are buffered by a rubber belt that absorbs impact.
In order to make the shell more solid, we decided to adopt a two-shot molding technique, which means one side of the shell is molded with the rubber belt together simultaneously.
We were happy with the shell’s structural resilience in the torture tests, but the metallic paint job wasn’t holding up to abrasions as well as we had hoped. We were building the A-Series to stand up to life’s challenges, and we wanted it to look good doing it. So we even had them revamp the paint formula a few times until we had something good enough to be a part of the A-Series. We also took the opportunity to play with a few different color options.
Our research showed that people were frustrated with batteries that didn’t live up to their rated capacity, so energy efficiency was very important to us. We wanted our total energy conversion rate (TECR) to be 80%, rivaling the industry standard of about 70%. After careful consideration, we agreed on an internal design that would meet our specifications. We decided we would spend the extra money needed to get the best components, starting with the internal batteries.
The lithium-ion batteries inside the A-Series are produced by a skilled manufacturer with an international reputation for high quality. Their batteries are energy dense and very reliable.
The essential charging and discharging operations of the Zendure A-Series battery are expertly coordinated by a control chip. Decades of research into secondary batteries has been distilled into this tiny marvel. The result is an amazing boost to efficiency that fits into a space the size of a pill.
The battery’s internal design uses thermal conductive silicone pads and a metal lining to draw heat away from the circuitry and make the whole system even more efficient.

We finally had a functional prototype that worked as well as the thing we imagined in our heads. Suddenly, it all felt so real.

From there, the manufacturer began developing the molds. As two-shot injection molding is an extremely complicated process, this task took more than two months, but it’s crucial work.
This was our first product, so it had to make a really good first impression and present our name, Zendure, in a way that would instill confidence in our ability to deliver a quality item. A lot of our competitors screen print their logos on their products. We wanted to do something different. We found a supplier that does precise stainless steel stamping, and they made a logo plate to fit our molded prototype perfectly. The result is a clean, impressive, and unforgettable introduction to who we are and what we’re all about.

The Zendure A-Series is uniquely great, and we built it just for you.

About Zendure Founders 

Bryan Liu is the Chief Executive Officer of Zendure, as well as the lead designer for the A-Series external battery. He came up with the basic structural and electronic concept of the A-Series and coordinated the launch of Zendure’s flagship product. He brought together the various engineering and manufacturing resources that were involved in the development process, and he constantly keeps in contact with all of us to make sure we’re sticking to our launch timeline.

Bryan’s lifelong fascination with electronics is due in part to his father, who was a self-taught electrical engineer. Bryan studied Information Technology in college. For the past decade, he has held senior marketing and product development roles in a number of reputable engineering and technology firms, including Halma, Ocean Optics, and a Siemens distributor in China.

Tom Haflinger is Zendure’s Chief Marketing Officer. His responsibilities include marketing, public relations and web development, as well as business administration. Tom conducted the consumer focus groups that helped us define our objectives. Tom’s parents both have a great deal of experience in electronics design and manufacturing, so Tom has always been fascinated with gadgets. He has worked in product development for Eastman Kodak, retail services for Apple and spent several years as a professional web developer and photographer.

Why "Zendure"?

The name "Zendure" is a combination of "Zen" and "endure". High-quality products endure a number of threats. Not just physical threats from accidents or rough storage, but also age. Quality products last a long time. The "Zen" prefix was chosen because it's a word that people often associate with a gentle nature. Our aesthetic designs are meant to communicate durability, but not in an aggressive way. Resilience, but not "military grade".