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Foldable phones have historically struggled to match the battery life of traditional slab smartphones due to their complex hinge mechanisms and large displays. However, recent advancements in silicon-carbon battery technology and power-efficient processors have significantly improved performance, allowing many of the latest models to last through a full day of use.
Book-Style Foldable Performance
CNET evaluated five book-style foldable phones in 2026: the Samsung Galaxy Z Fold 8, Z Fold 8 Ultra, Motorola Razr Fold, Google Pixel 11 Pro Fold, and the Apple iPhone Duo. Testing involved a 3-hour streaming video session and a 45-minute endurance test—covering social media, gaming, and video calls—conducted on each device’s inner screen while connected to Wi-Fi.
The $1,999 Apple iPhone Duo secured the top spot in CNET’s testing. Despite being Apple’s first entry into the foldable market, the device utilized its dual-cell battery design and the A20 Pro chip to achieve the highest average score. It finished the endurance test with 99% battery remaining and the streaming test with 84%.
Motorola’s Razr Fold followed closely, featuring a 6,000-mAh silicon-carbon battery. Samsung’s Galaxy Z Fold 8 and Z Fold 8 Ultra also performed well, standing out for their thin profiles—measuring 4.5mm and 4.1mm thick when unfolded, respectively. The Google Pixel 11 Pro Fold rounded out the group, showing strong performance in short-burst endurance tasks, though like its competitors, it saw higher battery drain during prolonged streaming.
Clamshell Foldable Performance
For users preferring a more compact, nostalgic design, CNET tested several clamshell devices, including the Motorola Razr series and the Samsung Galaxy Z Flip 8. These phones utilize smaller displays, which helps them maintain competitive battery life despite having less physical space for internal components.
The baseline Motorola Razr, priced at $800, achieved the best average score among flip phones. It led the 3-hour streaming test and tied with the $1,500 Razr Ultra in the endurance category. Other models, including the $1,100 Razr Plus and the $1,200 Samsung Z Flip 8, performed in close succession. The widespread adoption of high-density silicon-carbon batteries across these models has allowed manufacturers to pack more capacity into smaller dimensions.
Battery Life and Practicality
The testing results indicate that foldable phones are no longer just niche novelties but have become practical daily drivers. The Apple iPhone Duo, for instance, ranks among the top five phones tested by CNET this year across all categories, including traditional slab phones. While the iPhone 18 Pro Max holds the overall lead, the gap between foldables and standard devices has narrowed significantly.
As battery performance becomes more consistent across the industry, consumers can now prioritize other features such as camera quality, design, and price when selecting a device. CNET’s data suggests that the versatility of switching between dual displays no longer requires a compromise in battery longevity, as these devices are now capable of handling intensive tasks like gaming and streaming throughout the day.
