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ZDNET’s key takeaways
- No power bank combines 65W wired and 15W magnetic wireless charging.
- Engineers say existing battery cells easily handle these loads.
- Brands blame low market demand due to slow-charging flagships.
I recently started packing for a months-long staycation on a remote Pacific island where tech, power, and internet are scarce and expensive. I realized I’d need a capable power bank, because my Nothing Phone 3 typically lasts just a day per charge, and I planned several multi-day rural expeditions. My phone supports 65W wired and 15W wireless charging and has a MagSafe-compatible case. So, I was looking for something to store 10,000mAh, with 65W wired discharge for my phone and at least 15W wireless with magnetic attachment. Support for the Qi v2.2 standard capped at 25W, commonly marketed as Qi2, would’ve been ideal.
Disappointment ensued: I didn’t find a single power bank on the market that met my deceptively simple requirements. As relaxed as they are — any battery capacity, 15W wireless without MagSafe, and 65W wired charge/discharge — I couldn’t find a single product, current or dated, that worked. Everything online and in stores advertised 15W magnetic wireless charging with wireless capped at a mere 25W to 45W.
Larger batteries meant for laptops offered way faster wireless charging and multiple outputs, but skimped on wireless support entirely. Surely I cannot be the only one seeking such a power bank. The tech isn’t lacking either, given that my phone’s battery is built to accept 65W wired or 15W wireless and power banks for laptops are comfortably exceeding the 65W discharge rate I seek.
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To satiate my curiosity, I reached out to several accessory brands and the Wireless Power Consortium responsible for Qi standards. I’m still yet to buy a power bank. But I did learn what’s likely holding brands back.
Wireless charging isn’t optimal for travel, though
First, I want to address two frequent concerns with wireless charging in power banks. In a strictly technical sense, you’re better off using wired charging when you’re stuck in the middle of nowhere. It maximizes conversion of the battery’s stored charge into usable juice for your phone, unlike wireless charging, which draws more power from the battery than it delivers to the phone. That’s because wireless charging necessitates greater losses in transmission — the distance between the charging coils wastes heat.
However, wireless charging is still incredibly convenient for staying fully charged on tabletops and in urban areas where you’ll have the chance to recharge soon. Throw MagSafe and Pixelsnap in the mix, and the allure of convenience grows because the battery piggybacks onto the phone, even if the overall charging rate is slower for the power bank and phone. Brands like OnePlus have also surpassed Qi2 charging using a proprietary mix of active cooling, unique induction coil configurations, and custom hardware.
With that said, I was still struggling to see why we cannot offer the necessity of fast wired charging and the convenience of slower wireless charging in tandem on the same device, even if I ignore fast wireless tech for now. They exist independently, but never together. That’s evidence enough that current battery tech isn’t a hindrance to executing what I’d call progress for smartphone accessories.
It can be done – why no one has
Barry Phillips, head of product management at Apple-focused accessories brand Satechi, told me that “there’s no fundamental barrier” to building the power bank of my dreams, “even with support for Qi2, USB-PD, PPS, Adjustable Voltage Supply (AVS), and Extended Power Range (EPR) where applicable.”
“GaN continues to improve power conversion efficiency and reduce heat, while higher-performance lithium-ion battery cells continue to advance and emerging solid-state technologies are beginning to enter commercial applications,” he said, justifying the preface.
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Outlining these requirements, Phillips added that cells selected for this application will need a high continuous discharge rate for fast wired charging, low internal resistance, good thermal performance for wireless charging, long cycle life, and high energy density as a secondary consideration for pocketability. As such, industrial and military-grade Lithium Titanate (LTO) cells can be ruled out, considering their abysmal energy density, despite stellar thermal efficiency and discharge stats.
That leaves the industry with various Li-ion chemistries to choose from — options already popular for power banks. Cells with a Lithium Nickel Manganese Cobalt Oxide (NMC) cathode remain the best choice, and they’re already deployed in everything from smartphones to EVs. Phillips said Lithium Nickel Cobalt Aluminum Oxide (NCA) and Lithium Manganese Oxide (LMO) cells are also viable chemistries; the latter is well known for thermal stability in power tools, and the former for high-density cells that cost a premium.
Fellow tech journalist and FPV drone builder Nachiket Mhatre highlighted a critical difference in the physical architecture for cells, too. He said pouch cells used in FPV drones and power tools (and their low-discharge-rate variants used in smartphones) are lighter, costlier, space-efficient, and rated for higher discharge rates than cylindrical cells used in mainstream power banks.
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However, pouch cells have a lower energy density (charge held per unit volume), which explains why cylindrical batteries hold much more capacity in the same volume. Energy density is the obvious cornerstone for battery packs, and cylindrical cells are the de facto standard. Mhatre emphasized that a high continuous discharge rating of 65-140W, which a pouch cell could comfortably handle, typically entails high current draw, which generates heat and necessitates tabless cells. They replace thin metal strips between electrodes with a continious connection along the cell’s length, reducing internal resistance and distributing the heat generated from high-current application that could re-flow solder points.
While these power bank cells can handle transient spikes and short, high-power bursts, manufacturers would incur considerable per-unit costs. At scale, these costs add up fast.
Outdated flagships set the tone
Economies of scale aside, Phillips reiterated that ultimately, the connected phone controls charging, not your power bank. So, while the cells advertise the best technical capabilities, your handheld will negotiate the voltage and current it accepts through USB PD/PPS and other standards.
“Today, market demand — not engineering capability — is the primary constraint,” Phillips explained. “If Apple, Google, Samsung, or other OEMs released devices tomorrow that genuinely required those simultaneous power levels, companies like Satechi could develop a solution relatively quickly using technologies that are already commercially available.”
However, if you look at the current lineup from these companies, you’ll find Qi2 support paired with negligibly faster wired charging hovering around the 45W mark. I should emphasize that’s the peak wattage these devices would draw, and charging rates usually climb gradually to preserve battery health. This holds true for the newest releases, such as Google’s Pixel 11 series, with the Pro XL topping charts at 45W, even with the much-hyped Extreme Charging Mode enabled. Samsung’s Galaxy Z Fold 8 Ultra is also capped at 45W wired and 20W wireless charging. Meanwhile, my Nothing Phone 3, costing less than half as much, supports 65W with PD, PPS, QC3.0, and 15W wireless.
Sure, I didn’t compare apples to apples. But Satechi and other brands rely on flagship phones to set the standard for accessory specs. Moreover, Nothing remains an emerging brand with an abysmal presence in the Americas, potentially justifying power bank makers’ point that the market for what I seek isn’t there yet. Perhaps it’s time to ask why the Big 3 among smartphone makers still offer such slow wired charging alongside Qi2 support when several Chinese brands have long quashed concerns with much faster charging in consumer hardware.
The Wireless Power Consortium’s Qi Specifications Work Group chair refused to provide inputs for this story, even though most major consumer tech brands are on the Consortium’s board. I will prod that bear another day, but for now anyone in my shoes will just have to buy two power banks — one with Qi2 wireless, and another for fast wired charging. Consumerism triumphs this time.
