OnePlus did a remarkable job designing the OnePlus Open, the company’s first foray into the foldable phones space. With its razor thin profile and lightweight package, it’s almost unbelievable to wrap our head around the fact that this is a first generation model.
So it makes sense to wonder whether OnePlus had to scale back on the battery in order to achieve its impressive design. The short answer to that is no. That’s comforting because foldables aren’t known for their endurance. However, it seems that battery life in foldable phones continues to improve with each new generation — and the OnePlus Open is an example of that.
Rival devices such as the Samsung Galaxy Z Fold 5 benefit from the years of research and development with past phones, while newer ones like the Pixel Fold show how a chipset’s power efficiency could be the difference. In our OnePlus Open review, we ran our custom battery benchmark test to see exactly how long it takes its battery to tap out, along with how fast it can recharge using the included charger.
The results are surprising, which is part of the reason why the OnePlus Open is the best foldable phone around.
How test battery life
We put each phone we review through the Tom’s Guide battery test, which involves continuous web surfing over 5G at 150 nits of screen brightness.
In order to get a reliable rating, we run this test several times and get an average time based on those results. We run these tests with the phone's default refresh rate and the standard 60Hz. Higher refresh rates are generally more demanding,
We also test to see how quickly phones recharge. For the OnePlus Open, we used the included 80W SUPERVOOC power adapter — even though the phone itself supports 67W charging.
Phones are typically drained when we perform this recharge test, then we proceed to mark how much of a charge it has after 15 and 30 minutes of being plugged in.
OnePlus Open battery tests — the results
| OnePlus Open | Galaxy Z Fold 5 | Pixel Fold | |
| Battery size | 4,805 mAh | 4,400 | 4,355 mAh |
| Battery life (Hrs:Mins) | 11:45 | 11:25 | 9:46 |
| Wired Charging | 67W | 25W | 30W |
| Recharge percentage (15 mins) | 50% | 26% | 26% |
| Recharge percentage (30 mins) | 85% | 55% | 55% |
Since this is OnePlus' first foldable phone, we’re comparing it to its most direct rivals — which are the Samsung Galaxy Z Fold 5 and Google Pixel Fold. They both have a similar book-style design that matches the OnePlus Open.
OnePlus was able to somehow engineer its foldable phone to accommodate a hefty 4,805 mAh. That’s a step above what’s in the Pixel Fold and Galaxy Z Fold 5, which have 4,355 mAh and 4,400 mAh batteries, respectively. Due to this, the OnePlus Open is able to outlast its rivals in the battery life department.
In fact, its time of 11 hours and 45 minutes is better than the 11 minutes and 25 seconds posted by the Galaxy Z Fold 5, which previously held the title of longest battery life in a foldable phone. And furthermore, the OnePlus Open easily outlasts the Pixel Fold by nearly two hours running the same test.
This also holds true with our real world, day-to-day use with these foldable phones. On most nights since we’ve started to test out the OnePlus Open, we’ve consistently seen it at around 10% battery capacity before bedtime. It might not sound like a whole lot, especially when we’ve seen traditional flagship slates around 15%, but it’s a great step in the right direction for a foldable.
What’s even more astounding is the speedy recharge time of the OnePlus One. It’s not a competition at all as you can see from the chart above. Using the included 80W SUPERVOOC power adapter, the OnePlus Open’s 67W wired charging via USB-C gets it up to 50% after 15 minutes charging — and nearly a full charge at 85% after 30 minutes.
In contrast, the Pixel Fold and Galaxy Z Fold 5 are significantly slower. However, you should know that those foldable phones also offer the convenience of wireless charging, which isn’t available in the OnePlus Open.
OnePlus Open battery life outlook
Battery life has long been one of OnePlus’ strongest areas, so it should come as no surprise that it’s excellent with the OnePlus Open. Even better is how the company is able to balance things out because larger batteries tend to be accompanied by bulkier designs. Yet, OnePlus was still able to engineer a foldable phone that’s razor thin and lighter than everything else out there.
We still wish the OnePlus Open had wireless charging, especially when you’re paying so much for a phone. Yes, it’s wicked recharge speed is consolation for this missing convenience, but wireless charging is one of those features we expect to get in a premium priced smartphone.
Regardless of that, you won’t be disappointed by its battery life.
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