openbattery

README

⚡ openbattery

A beautiful, responsive macOS terminal battery monitor built with Bubble Tea.

Watch your battery level, power draw, discharge estimates, and health stats in real time — right from your terminal.

Features

• Live dashboard — battery percentage with gradient progress bar, power draw (watts), remaining time, and charge estimates
• History sparkline — ▁▂▃▄▅▆▇█ chart of battery level over time with Y-axis labels and time range
• Smart estimates — remaining time calculated from your average power consumption (last hour / today)
• Battery health — current max capacity vs design capacity, cycle count
• Two tabs — 1 for dashboard, 2 for history, r to refresh, q to quit
• Responsive layout — adapts seamlessly to any terminal size
• Persistent history — saves up to 500 samples to ~/.openbattery/history.json
• Zero config — just run it, no setup needed

Installation

go install github.com/przybylku/openbattery@latest

Or clone and build:

git clone https://github.com/przybylku/openbattery.git
cd openbattery
go build -o openbattery .
./openbattery

Requires macOS (uses pmset and ioreg system utilities).

Data Sources

openbattery reads from two macOS system commands:

• pmset -g batt — battery percentage, charge status, Apple's time estimate
• ioreg -rn AppleSmartBattery — amperage (mA), voltage (mV), capacities (mAh), cycle count

All data is processed into a clean TUI with color-coded indicators:

Condition	Color
Battery ≥ 50%	Green
Battery ≥ 20%	Yellow
Battery < 20%	Red
Charging	Cyan
Charged	Green

History

Every 10 seconds, a data point is appended to ~/.openbattery/history.json (keeps last 500 entries). The history tab renders a sparkline of the last 60 samples with the most recent 10 displayed in a table.

License

MIT