# How to Choose a Phone Case That Won't Slow Down Wireless Charging The wrong case can cut your wireless charging speed in half. - **Source:** [Engadget](https://www.engadget.com) - **Published:** 2026-08-07 - **Original article:** - **On Brifing:** https://brifing.si/s/bee1fc0b-841b-448c-8cf7-604b699e8b36 ## The Evolution of Wireless Charging Wireless charging debuted in 2009 on the Palm Pre. Nokia Lumia 920 became the first Qi-standard phone in 2012. Apple's MagSafe reintroduced magnetic alignment with iPhone 12 in 2020. Today's Qi2 standard reaches 25W speeds, still just one-third of wired charging capabilities. This technology has seen gradual improvements over 15 years. ## How Cases Impact Charging Efficiency Thick cases can slow energy transfer by up to 50%. Metal components may block charging entirely, while misplaced magnets disrupt connection. Spigen's tests show TPU cases thicker than 3mm double charging time. Excessive heat buildup can even melt phone adhesives, as reported by Galaxy S25 Ultra users experiencing compromised water resistance. ## Critical Material Considerations Cases like Speck Presidio 2 with coil cutouts reduce plastic layers. Thin TPU cases (0.5-1mm) deliver best performance. For phones like Samsung S26 Ultra lacking built-in magnets, Qi2-compatible cases add magnetic functionality. Back accessories like PopSockets create additional thickness issues, with some third-party grips causing alignment problems. ## Choosing Magnetic Cases Wisely Qi2-certified cases guarantee proper magnetic alignment. However, removable magnetic accessories like OhSnap Snap Grip may loosen over time. Spigen MagFit offers reliable performance with fixed magnet rings. For car chargers, hinge durability becomes crucial - some cases disconnect during vehicle vibration according to user reports. ## Performance Comparison of Popular Cases Testing shows Speck Presidio 2 maintains 18W speeds exceptionally well. Spigen Thin Fit series provides fastest charging at just 1.2mm thickness. Apple's official MagSafe cases cap at 15W, while third-party Qi2 cases achieve 25W. Samsung's official cases support their proprietary 15W fast charging protocol but limit Qi2 compatibility. ## Thermal Management Tips Wireless charging can heat phones up to 40°C. Dual-layer cases like Otterbox Defender trap heat, reducing efficiency. Removing cases overnight extends battery life. ESR HaloLock cases with air vents show best thermal performance in tests. Extreme heat can compromise water resistance, as seen in some Galaxy S25 Ultra incidents. ## Smart Purchasing Strategies Filter Amazon reviews for 'wireless charging' experiences. Search YouTube for '[case name] + Qi2 test' videos. Test demo units in stores with your phone. Avoid thick cases for phones with 5000mAh+ batteries. Choose fixed-magnet cases for car charging, ultra-thin designs for office use. Verify return policies before purchasing. ## Future Technology Outlook The upcoming Qi3 standard promises 45W wireless charging by 2025. Xiaomi's 80W air charging prototype tests non-magnetic distance charging. Research indicates graphene-enhanced cases dissipate heat 30% better. Apple's patent filings suggest future iPhones may incorporate case-free magnetic charging, potentially revolutionizing accessory compatibility. ## Sources covering this story - https://www.engadget.com/2228889/why-phone-case-type-works-best-for-wireless-charging/ — --- _Summary written by Brifing from the original reporting. Copyright in the original article belongs to its publisher; read the full piece at the link above._