Microsoft says that Battery Limit is made for Surface Pro models that are plugged in most of the time. As an example, the company mentions a setup in a kiosk where a Surface Pro unit could be constantly hooked up to an outlet. While the feature is currently available for the Surface Pro 3 and Surface Pro 4 only, Microsoft plans on adding it to other Surface Pro models in the future.
On the Surface Pro 4, Battery Limit is toggled on by booting into Surface UEFI (Power and Volume up when turning on the device). Select Boot Configuration > Advanced Options and toggle Enable Battery Limit Mode to On. On the Surface Pro 3, boot into Surface UEFI. Go to Kiosk Mode > Battery Limit > Enabled.
For more information on Battery Limit, check out Microsoft’s support page by clicking on the sourcelink below.