Yesterday, Apple released a new firmware update. MagSafe Battery Pack official And it turns out that the new firmware allows 7.5W charging on the go, up from the previous 5W limit.
In its support document, Apple says MagSafe Battery Pack owners can update the firmware to the new 2.7.0b.0 to get faster 7.5W charging capability.
Updating MagSafe Battery Pack can be done either by connecting an iPhone and waiting (a process that can take up to a week), or using a Mac or iPad to update in five minutes. Apple recommends that users connect a Lightning cable to MagSafe Battery. Pack and plug the USB side into an iPad or Mac to begin the update process.
And you can check which firmware version is MagSafe Battery Pack Your iPhone is working by connecting to iPhone, then going to Settings > General > About > MagSafe Battery Pack. You’ll need version 2.7.b.0 to get 7.5W charging.