OPPO is pretty big on the ‘5-min charge, 2-hr talk’ tagline for the OPPO F9. The company claims that the phone’s VOOC Flash Charge technology can provide up to 2 hours of voice calls with merely 5 minutes of charging.

However, there’s a disclaimer on the company’s official website. Let’s break it down into three parts and see if the phone can achieve the 2 hour talk time in real life.

 

OPPO F9 Disclaimer

5 minutes of charging supports 2 hours of talk time: Test environment: temperature of 20°C – 30°C, relative humidity 45% – 75%, pressure of 86 – 106 kPa. Test conditions: All applications and functions except those for normal calls & VoLTE voice calls are turned off with 1% power remaining in the mobile phone battery, and use a standard power adapter to charge for 5 minutes. After charging, answer a phone call for 2 hours in a black screen with call volume at 50% at a place where the available mobile phone signal is maximum. Actual talk-time may vary depending on the specific conditions of the phone.”

 

Part 1: Test Environment

The Philippines has an average temperature of 26.6 °C which is within the quoted temperature range of 20°C – 30°C of the test environment. Charging the phone while the room temperature is lower means charging time becomes shorter.

Next, we have the humidity which is the same as atmospheric moisture. It means the amount of water vapor in the air. Sadly, the Philippines has a high humidity of up to 85% in the rainy season. It’s slightly higher than the 75% maximum humidity of the test environment but the difference isn’t significant.

Lastly, there’s no problem with the atmospheric pressure since it only varies with elevation.

 

Part 2. Test Conditions when Charging the OPPO F9

This is the part where the OPPO F9 is charged for 5 minutes. All apps and functions of the phone except for calling are turned off. The device automatically enters a low power mode when hitting 20% battery life.

However, it’s worth noting that they didn’t re-charge the phone starting at 0% battery life during the test. Instead, they re-charged it with 1% of battery life.

It’s only logical that charging a fully drained OPPO F9 for 5 minutes won’t result in 2 hours of talk time since the test had a head start of 1% battery life. It should be slightly lower.

 

Part 3. During the OPPO F9 Call

The call started immediately after charging the OPPO F9 for 5 minutes. Its screen is turned off which normally happens when we put the phone near our ear.

However, they set the volume of the phone to 50% during the test. On the other hand, I usually set the volume to 100% when answering a call. This affects the battery life.

Lastly, they conducted the test at a place where the cellular signal is at maximum. The weaker the cellular signal, the more power will be consumed by the phone trying to connect to the cellular network.

 

Results may vary

The OPPO F9 can achieve 2 hours of talk time with 5 minutes of charging in ideal conditions. The Philippines meet most of the testing conditions but the phone should be re-charged with 1% battery life left, not when it’s fully drained. Furthermore, the phone’s volume should only be at 50% during the call while the cellular signal is at maximum.

The OPPO F9 can achieve 2 hours of talk time with 5 minutes of charging in ideal conditions.

I might be able to test this myself when I get an actual unit of the OPPO F9.

For now, I’m happy that OPPO added fast charging to the OPPO F9. However, the numbers that they are claiming might be a little too optimistic. Still, I’ll be happy if a phone lasts more than an hour after a 5-minute charge.


OPPO F9 specs:

Average rating of 4.1 stars from 35 users.
  • 6.3-inch FHD+ LTPS Display (1080 x 2340 Pixels), 409 ppi
  • Android 8.1 Oreo Operating System
  • Mediatek Helio P60 Chipset
  • 6 GB
  • 16 + 2 Megapixel Rear Camera with LED Flash
  • 25 Megapixel Front Camera
  • Dual SIM
  • 64GB Internal Storage
  • Expandable Up to 256 via microSD
  • 4G LTE, 3G HSPA+, 2G EDGE & GPRS Networks
  • Wi-Fi 802.11 b/g/n/ac (Dual Band)
  • Bluetooth 4.2
  • MicroUSB 2.0
  • 3.5mm Audio Jack
  • Fingerprint Sensor
  • 3500mAh Battery
  • VOOC Flash Charge (5V/4A)
  • 17,990.00 Official Price in the Philippines