TrayBatt – Laptop battery monitor

This program is designed to obtain information about the laptop battery using a standard Power Management API (Windows Battery API) – structures BATTERY_INFORMATION, BATTERY_STATUS.
In addition, TrayBatt works with UPS supporting UPS Smart Battery standard.
Displaying: battery level, declared capacity, actual capacity, level of destruction, voltage, rate charge or discharge, temperature of battery, model, serial number of battery, other parameters and statuses battery which it reports.
Capacity level, voltage, remaining time (calculated based on the estimated capacity and current rate) – can be displayed in the system tray.
If you hover your mouse over the displayed values, a tooltip with a short description of this value will be displayed.

Screenshot - Main screen TrayBatt, when powered by ACScreenshot - Settings TrayBatt

The standard icon of the Windows battery indicator in the tray on many laptops shows (in the tooltip) the estimated operating time is incorrect. Because in reality the estimated battery life in a laptop depends heavily on the level of the backlight, the load on the processor and other factors. The standard Windows battery icon uses the calculation of the operating time from the function GetSystemPowerState – and there for the time is used the calculation for the instantaneous load at the time of decreasing the capacity in percent. Those. The time calculation takes place every few minutes, but does not reflect the average load for these minutes.

TrayBatt when powered by a battery. Comparison of battery indicators in the tray - the moment of high load after idle timeTrayBatt when powered by a battery. Comparison of the battery indicators in the tray - the moment of low load after a high load

TrayBatt also does not calculate the average time, but does the calculation of the laptop’s operating time reserve by instantaneous load every second (more precisely, uses time polls through IOCTL_BATTERY_QUERY_INFORMATION – BatteryEstimatedTime). For example, changing the brightness of the backlight or running resource-intensive applications – you can immediately see how the load changes and what time is predicted.

All information (capacity, voltage, current rate) – this is what the battery itself reports. The capacitance readings can be very inaccurate, especially for an old battery. The built-in battery controller reports for example that the charge is full, and after a few minutes the laptop suddenly turns off due to a deep discharge (because the chemical elements of the battery are worn out, and the battery wear is not always predictable for self-diagnosis). So you can not completely trust the battery monitoring readings.

History of development program:
v.2.3 (2022.05.06) Improved error handling procedure, more informative error notifications;
Support for screens with DPI scaling (now fonts are not distorted);
Added check for availability of updates (only manually, from the About).
Various minor improvements.
v.2.2 (2021.02.18) Minor improvements;
v.2.1 (2017.11.11) Minor improvements;
v.2.0 (2017.08.01) Add tooltips, add poll GetSystemPowerStatus;
v.1.2 (2017.04.02) Updated list of battery chemistry codes;
v.1.1 (2016.12.17) Minor improvements;
v.1.1 (2016.10.31) First public version.


Download “TrayBatt_v230.rar” – 24.45 KBVersion 2.3.0.11, 2022-05-06

Download “TrayBatt_v220.rar” – 22.10 KBVersion 2.2.0.10, 2021-02-18