In-Car Wireless Charging: 25W Qi2.2 Standard Solves Frustration

In-car wireless chargers have long failed to satisfy users. While office wireless chargers could fully charge devices over extended periods, the situation in cars was different. Especially when placed on the dashboard or in front of the windshield, direct sun exposure caused charging speeds to drop significantly. As a result, they often only maintained the battery level rather than truly charging it.

The charging environment inside a car is very challenging. In addition to sun exposure, continuous screen usage for navigation simultaneously consumes power. Under these extreme conditions, even with existing wireless chargers, smartphone battery levels would merely maintain or increase only minimally, rather than charging significantly.

To overcome these limitations of in-car wireless charging, a new wireless charging standard was announced last year. After using products with this new standard for several months, they showed incomparably more effective charging performance than previous chargers. Therefore, consumers considering purchasing an in-car wireless charger should definitely check for this new standard before buying.

Currently, most wireless charging methods use 'Qi', an international standard set by the Wireless Power Consortium (WPC). This standard has long been applied to smartphone wireless charging, typically offering charging speeds of 5W to 15W. However, unlike wired charging, wireless charging transmits energy via magnetic fields, making heat generation and loss unavoidable. For this reason, even if the specifications state 15W, the actual charging efficiency is lower.

Wireless charging efficiency varies greatly depending on several factors, including the position and distance between the smartphone and charger, coil size, and any obstacles in between. These complex factors further exacerbate the inefficiency of wireless charging.

To improve the low efficiency of wireless charging, Apple introduced 'MagSafe' technology starting with the iPhone 12 series in 2020. MagSafe works by adding a magnetic ring to the smartphone to precisely align the charging coils, increasing charging efficiency, and offering versatility for various accessories using magnets.

Noting MagSafe's innovative concept, the Wireless Power Consortium (WPC) announced a new international standard called 'Qi2' in April 2023. Qi2 maintains the same 15W charging speed as before but newly added the 'MPP (Magnetic Power Profile)' specification. This MPP specification is essentially designed based on Apple's MagSafe structure.

Apple actively participated in Qi2 development as a WPC member and provided its MagSafe design to the consortium. This is interpreted as Apple's intention to make MagSafe technology more universally applicable to a wider range of devices.

Subsequently, on July 23, 2025, the Wireless Power Consortium achieved a groundbreaking advancement by releasing Qi2.2.1. This version boosts wireless charging speeds from the previous 15W up to 25W. While still slower than wired charging, the significantly increased speed demonstrates performance capable of largely replacing wired charging.

We compared the designs of five Qi2.2-supported wireless chargers (Jupazip, Mayton, Sinjimoru, Inside Edition, Arari) available on the market. Sinjimoru had a clean white front and a well-coated attachment area, indicating good quality. Mayton featured a clean matte black design without a logo but was somewhat bulky. Inside Edition and Arari had almost identical designs, while Jupazip showed a clean design similar to Sinjimoru. Notably, Jupazip cools using an air-cooling method with a fan, without a Peltier element.

We compared the actual charging speed difference between existing 15W chargers and the new 25W wireless chargers. Given that 15W chargers were already slow due to heat, questions arose whether 25W would generate even more heat and thus be practically meaningless, leading us to conduct this test.

The charging speed test was conducted with two devices that support up to 25W charging: iPhone 17 Pro Max and Galaxy S26 Ultra. For the test, one 15W charger supporting Peltier and Jupazip's 25W charger were used. To achieve optimal results, the test was performed indoors without air conditioning, at an external temperature of 36-38 degrees Celsius, instead of in an actual car environment. This was done to minimize the frequent variables of a car environment.

For the iPhone 17 Pro Max, the 15W charger took 1 hour and 51 minutes to fully charge from 0% to 100%. In contrast, the 25W charger completed charging in 1 hour and 36 minutes, showing a faster charging speed by about 15 minutes. The time to charge to 80% was also around 1 hour and 20 minutes for the 15W charger, while the 25W charger took less than an hour. This showed a clear difference in the graph. In an actual car environment, charging speeds can vary depending on various factors such as direct sunlight and air conditioner use.

For the Galaxy S26 Ultra, which lacks internal magnets, we used a Samsung official certified magnetic case to ensure accurate coil alignment for the test. For Galaxy, charging speed significantly slows down after 80%, so we only measured up to the 80% mark. The 15W charger took 1 hour and 14 minutes to reach 80%, while the 25W charger reached it in 44 minutes, showing a speed difference of over 30 minutes. While the iPhone tended to adjust its speed based on temperature, the Galaxy showed a nearly straight charging graph, suggesting potentially superior heat control capabilities and less variation in charging speed.

To provide more information than just a comparison of two products, we purchased and tested other 25W chargers available on the market, in addition to Jupazip. The selection criteria for additional products were limited to only those certified with WPC 2.2.

Upon reviewing the certification details of the chargers, most brands had unique certifications, but Inside Edition and Arari shared the same WPC and KC certifications. This suggests that both products are certified and sold by the same Chinese manufacturer. In fact, their external appearances showed almost identical internal structures, with only slight customization of the outer design. Arari had a urethane coating on the charging area, while Inside Edition was glossy, but buttons and fan structures were identical for both.

Comparing a total of five 25W chargers—Sinjimoru, Mayton, Inside Edition, Arari (newly purchased), and Jupazip (existing test product)—the charging speeds were mostly similar. For iPhone full charging time, the difference between the fastest and slowest product was about 6 minutes, a negligible difference within the margin of error. Galaxy's 80% charging time also showed a minor difference of about 6 minutes.

When measuring the coil temperature of each product during charging, most chargers maintained an internal temperature of 35-37 degrees Celsius. Jupazip showed a slightly higher temperature of 43 degrees, but this did not significantly affect charging speed. This difference is due to the cooling method: Jupazip uses turbine air-cooling, while the other products employ Peltier elements for cooling. Jupazip explained that they deliberately omitted Peltier elements to avoid issues such as reduced charging efficiency and increased product bulk that would arise from larger Peltier elements and higher power consumption at 25W output when heat increases.

The prices of the compared 25W chargers were mostly similar, ranging from the mid-30,000 won to early 40,000 won range. Among these, Sinjimoru offered the best value for money, costing 34,900 won including shipping. Arari, Mayton, and Jupazip were in the lower tier with prices exceeding 40,000 won including shipping.

To properly utilize a fast wireless charger, there are a few considerations. Accounting for power loss, the car charger (cigarette lighter adapter) should support at least 30W to 45W output, and the device to be charged, such as a smartphone, must also support 25W or higher wireless charging. While older in-car built-in wireless chargers or conventional wireless chargers had difficulty providing effective charging due to heat issues, the 25W Qi2.2 charger offers meaningful charging speeds, making it one of the most satisfying car accessories.