Surface Power Cover

I just picked up a couple of Surface Power Covers. They were on sale and it seemed to be good value to get them now. I run long Skype sessions with screen sharing and these chew up battery life. The Surface Power Covers help with that.

Power Cover

If you follow the instructions and remove the warning label on the connector, the Surface Power Cover works with Surface Pro 3 as well as the Surface Pro 2, Surface Pro, and Surface 2.  It  will work as a keyboard only for a Surface (RT) – the original.

You have to do a Windows Update to install the drivers that allow you to see all the battery information described in this article.

Surface Power Cover

Tap or click the battery icon in the desktop tray to see the charge on each battery.

The typing experience is pretty much the same as the original type cover and that’s a good experience. The overall experience is better with the Surface Pro 3 type cover with the bigger touch pad. But when battery life is a priority, I’ll make the sacrifice.

The early reports about usability of the touch pad have been alleviated by firmware updates that work on both Surface Pro and Surface Pro 3. That is, you can:

  • double tap for left-click
  • tap-drag to select and
  • two-finger tap for right-click

This pretty eliminates my need to use the buttons on the bottom of the touch pad except when I need to do a right-click drag.

I was concerned about the weight, but if I need longer battery life, I’m probably stationery. Walking around in tablet mode is a secondary concern. Traveling around I’ve found that the weight is no more a burden than carrying the power supply and it fits better in my carrying case.  It’s a relief not to be looking for power outlets before I stake out territory in a room

The Power Cover can charge the Surface while the Surface is in sleep or standby mode. That means that if I’m in an all day session where I need to walk around with the Surface, when I’m on a break, I can snap on the Power Cover and charge the Surface just like I would take those opportunities to connect it to a charger, only now I don’t need to find an AC outlet.

Here’s an excerpt from the article above describing the charging sequence.

Charging sequence

The Surface and Power Cover batteries are charged and discharged in a sequence designed to keep most of the charge on the Surface battery. Understanding the sequence makes it easier to predict how much charge to expect on each of the batteries.

Which battery gets charged first?

Once Surface is 80% charged, it starts charging the Power Cover. Then, when Power Cover is 80% charged, Surface finishes charging. When Surface is fully charged, Power Cover finishes charging. Power Cover will charge as long as Surface is turned on (sleep is fine) and connected to a power source, and Power Cover is connected to Surface.

battery charging sequence

How the batteries charge.

Which battery is used first?

When you’re using Surface and Power Cover and the Surface isn’t connected to a power source, Surface draws power from Power Cover first. When the Power Cover battery is drained, Surface switches to its own battery.

Power Cover continues to charge your Surface while it is in sleep or on standby. If Surface is turned off and unplugged, or the Surface battery is completely drained, it can’t detect the Power Cover or draw power from it.

If the battery on the Power Cover is completely drained, you can still use it as a keyboard.

So far, I’m very pleased with the Power Covers.

I have the Surface Pro and Surface Pro3 docking stations. It’s easy to connect the Power Cover to the Surface while docked, and that’s convenient for charging the Power Cover as long as the Surface is in sleep or hibernation mode. It doesn’t charge when the Surface is off.

Battery Life?

From what I can see using BatteryBar, it looks like the Power Cover offers about 29 mWh to the 42 mWh to the internal battery in the Suface Pro3 for a total of about 71 mWh.   I haven’t had occasion to exhaust the system to find out how long that actually lasts, but from what I’ve seen that should be more than enough to get me through 7  or 8 hours of connected work.  That’s pushing hard.