Caring for your Surface battery

About lithium-ion batteries

Lithium-ion batteries are the most common type of battery used in today’s portable devices. These batteries charge quickly, discharge deeply at a steady rate, and have high energy density that allows for small cell sizes. This makes them ideal for Surface devices where we design for the longest possible battery life in the smallest possible form factor.

Surface devices are engineered to maximize battery life and longevity. By understanding a little about lithium-ion batteries you’ll be able to help maximize the life and longevity of the battery in your Surface device: 

• It is common for the capacity of lithium-ion cells to diminish after a certain number of charge/discharge cycles. This will result in shorter intervals between charging and lower battery capacity.

• When using your device, make sure the battery drains below 50 percent regularly. This will help minimize aging of the battery cells.

• Surface devices have features to reduce battery aging. Keeping your device current with the latest driver and firmware updates is the best way to help preserve battery reliability and longevity.

How to maximize battery health

Like all batteries, lithium-ion cells are consumables that age and lose capacity over time and with usage. The best way to extend battery life and performance on devices that don't support smart charging is to drain the battery below 50 percent several times a week before recharging rather than discharging it on frequent short and shallow discharge cycles.

As you use your battery, there are some conditions you should avoid as they can lead to faster aging:

• Avoid using or charging at extreme high temperatures: Devices that are charged or operated at high temperatures will cause accelerated aging of the lithium-ion battery and permanent loss of battery charging capacity. Surface devices are designed to work between 32°F and 95°F (0°C-35°C) so keep your Surface out of the sun and don’t leave it in a hot car.

• Keeping or storing at a high state of charge: Batteries maintained at a high charge state will lose capacity faster. You can help prevent this accelerated process by not leaving your device connected to AC power for extended periods. Rather, try to ensure the device is regularly discharged below 50% before charging again. If you have a scenario where you need to keep the device plugged in continuously, we recommend using the Battery Limit Mode to limit the battery state of charge. If you need to store your device for a long period of time, it’s best to reduce the charge level to 50% before storing and to regularly check the battery to ensure it has not drained to very low levels.

When batteries experience excessive aging, you may see severe battery life reductions or advanced expansion of the lithium-ion cells. Under normal conditions, Surface devices are designed with a mechanical enclosure to contain battery expansion. Under extreme conditions the battery may expand beyond the mechanical limits of the device and result in deformation.

Advanced battery expansion caused by excessive aging does not present a safety concern and is most often caused by the formation of non-flammable carbon dioxide (CO₂) gas. If you have a device where the battery has expanded visibly beyond the mechanical enclosure, we recommend you stop using the device. You should handle the device with caution to prevent putting pressure on or risk puncturing the battery cell. If you need assistance, please complete the Surface replacement request form to work with a Surface Support Advocate.

Surface features to optimize your battery longevity

Surface is continually working to help get you the most from the battery in your device and regularly releases fixes designed to improve battery reliability and longevity. The following features are already available on select device models (see table below) to help deliver optimal battery performance and slow down battery aging:

• Battery Smart Charging – Battery Smart Charging is a feature that helps protect your battery from the effects of charging patterns and high temperatures that may accelerate battery aging or lead to expansion. Battery Smart Charging is always active and turns on automatically to limit battery charging to 80% when it detects your device is plugged in for prolonged periods and/or used at elevated temperatures. The 80% charging limit automatically turns off when the battery has been discharged below 20%. What you see when Battery Smart Charging turns on depends on your Surface device model. For specific details, see Feature availability below.

• Battery Limit Mode - Battery Limit Mode is a feature available for users who need to keep devices plugged in for extended periods of time. Plugging in the device for extended periods of time can cause batteries to prematurely age. When enabled this feature limits battery charging capacity to 50%, which slows the aging process and prolongs battery longevity.
  
  More details on Battery Limit Mode, including instructions to enable and disable the feature, can be found on our Battery Limit Mode support page.

• Battery Lifespan Saver - Battery Lifespan Saver is a feature designed to help protect your battery from the cumulative negative effects of consistent and recurrent use at high temperatures or high states of charge. This feature complements Battery Smart Charging by monitoring battery conditions continuously. If these adverse conditions are detected, Battery Lifespan Saver implements a limited number of permanent reductions in charging voltage. Although this will result in a small incremental and permanent loss to battery capacity, it will maximize the total lifespan of your battery by addressing conditions that would otherwise accelerate battery aging, significantly reduce battery capacity, or lead to battery expansion.

To get the most from these features, it's important to keep your device current with the latest driver and firmware updates.

If you normally connect to Windows Update and use the default out of the box settings to receive automatic updates, you’ll always have the latest drivers and firmware. For more info, see Get the latest Windows update.

You can quickly check the health of your Surface drivers and firmware using the Surface app.

Open the Surface app

1. In the Surface app, expand Help & support to check the update status.

2. If there are updates available, select the Check for updates button to open Windows Update and install the available updates. 

   : If you don't have the Surface app installed, you can download the Surface app from the Microsoft Store. When it has downloaded, select Start, search for Surface, then select the app from the list of results.

If your Surface device is managed by your organization, your IT group will typically deploy updates internally.

Feature availability