AJ28 Magnetic Wireless Power Bank with Digital Display | OEM

Frequently Asked Questions: AJ28 Magnetic Wireless Power Bank with Digital Display

1. How accurate is the digital battery display on the AJ28 and what does it actually show?

The AJ28 features a precision digital display that shows the exact remaining battery percentage in real time, from 0% to 100%. Unlike simple 4-LED indicators that only give rough 25% increments, the digital readout lets you know precisely how much power is left before you head out. The display refreshes every few seconds during charging and discharging, so you always have an accurate snapshot of your current power level. This is especially useful for B2B buyers who need to inventory and track the charge status of multiple units before distribution.

2. Can I use the magnetic wireless charging and the built-in Type-C cable at the same time?

Yes. The AJ28 supports simultaneous wireless and wired charging, allowing you to power two devices at once — one magnetically attached on the wireless surface and another connected through the built-in Type-C cable. When both outputs are active, the total output is intelligently distributed to maintain stable charging speeds without overheating. This dual-output design makes the AJ28 particularly versatile for users who carry both a MagSafe-compatible iPhone and a USB-C device such as an Android phone, iPad, or wireless earbuds case.

3. Why does the AJ28 use a square form factor instead of the typical rectangular power bank shape?

The compact 75×64×25mm square design is intentional. A square footprint distributes weight more evenly than a long rectangular body, which means the AJ28 sits more securely on a flat surface when a phone is magnetically attached on top. The symmetrical shape also prevents the power bank from wobbling or tipping when your phone is charging wirelessly in portrait or landscape orientation. At just 40g, the square body is pocket-friendly and pairs naturally with smaller phones without extending beyond the device’s edges.

4. What are the 105555 battery cells and why did YULIDA choose them for the AJ28?

The AJ28 uses two 105555 polymer lithium cells to achieve its 10,000mAh capacity in such a compact body. The 105555 format (10mm thick, 55mm × 55mm) is a square pouch cell that offers higher volumetric energy density than cylindrical 18650 or 21700 cells. This means more battery capacity fits into less physical space, which is why the AJ28 can deliver 10,000mAh in a 75×64×25mm body that weighs only 40g. Pouch cells also have lower internal resistance, resulting in less heat generation during fast charging and longer overall cycle life.

5. How does the 20W PD fast charging perform with the latest iPhone and Android models?

The AJ28’s Type-C port and built-in cable both support 20W PD output (5V/3A, 9V/2.22A, 12V/1.67A), which is the optimal charging speed for most current smartphones. For iPhones that support USB-PD, the AJ28 can charge from 0% to approximately 50% in about 30 minutes. For Android devices supporting QC or PD protocols, the AJ28 negotiates the fastest safe charging rate up to 20W. The 9V/2.22A profile is particularly well-matched for devices like the Samsung Galaxy S series and Google Pixel lineup, delivering near-maximum charging speeds without requiring a separate wall charger.

6. How does the magnetic wireless charging alignment work with different phone sizes and cases?

The AJ28 uses a precisely positioned magnetic coil with N52 neodymium magnets that align automatically with MagSafe-compatible iPhones (iPhone 12 and later). The magnetic ring is engineered to snap into the correct charging position without manual adjustment, ensuring optimal coil-to-coil alignment for maximum charging efficiency. For non-MagSafe phones, the flat wireless surface still supports Qi charging at up to 15W — simply place the phone centered on the surface. We recommend using cases thinner than 3mm for reliable wireless charging; thick rugged cases or metal-backed cases may reduce charging speed or prevent magnetic adhesion entirely.

7. What OEM customization options are available for the AJ28’s digital display and overall design?

For OEM/ODM orders starting at 500 units, YULIDA offers extensive customization for the AJ28. The digital display can be programmed to show your brand logo during startup, custom battery icons, or alternate between percentage and voltage readings. The exterior supports full-color logo printing, UV printing, or embossed branding on the magnetic surface and side panels. Packaging options include retail-ready gift boxes, blister packs, or eco-friendly kraft boxes with your branded insert cards. The built-in Type-C cable color, shell color (standard black or white), and even the magnetic ring orientation can be tailored to match your brand identity. All customized units undergo the same 28-point quality inspection and 72-hour aging test as standard production models.