diff --git a/battery-monitor.sh b/battery-monitor.sh
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+#/bin/bash
+
+# battery-monitor.sh
+# This program lets the user know when the battery needs to be charged.
+# Copyright (c) 2024, Scott C. MacCallum (scm@sdf.org).
+# All rights reserved.
+
+# Redistribution and use of this software in source and binary forms, with or
+# without modification, are permitted provided that the following conditions
+# are met:
+
+# * Redistributions of source code must retain the above copyright notice,
+#      this list of conditions and the following disclaimer.
+
+# * Neither the name of Scott C. MacCallum nor the names of its
+#      contributors may be used to endorse or promote products derived from
+#      this software without specific prior written permission of Scott C.
+#      MacCallum.
+
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+
+# Change this variable to your batteries identification e.g. BAT0
+
+battery=""
+charge=$(cat /sys/class/power_supply/$battery/charge_now)
+discharge=$(cat /sys/class/power_supply/$battery/current_now)
+hours=$(echo "scale=2; $charge / $discharge" | bc -l)
+minutes=$(echo "scale=2; $hours * 60" | bc -l)
+minimum=0.33
+
+# If the battery has 15 minutes left of charge, let all users know
+
+if (( $(echo "$minutes < $minimum" | bc -l) )); then
+    echo "Recharge battery!" | wall
+fi
+
+exit 0