Bathealth - Shows live info and statistics about a Lenovo Thinkpad battery

bathealth

#!/bin/bash

# Bathealth - Shows live info and statistics about a Lenovo Thinkpad battery
# By Chris Mavrakis - cmavrakis.com
# v0.3 - 6-May-15

# Usage:
# - Install in /usr/bin or ~/bin, or not...
# - Run as a normal user: bathealth or ./bathealth

############## FUNCTIONS ############## 
# Gets a file ($1), a description ($2) and a unit ($3) and retrieves the value from the file and prints it. No return.
function myprint {
    tmp=`cat $bat0/$1`
    # Check if we were asked to print the State of charge
    if [[ "$2" != "SOC:" ]]
    then
        # If not, do a division (usinb bc), set some colors and print everything together
        echo $2 ${green}`echo "scale=2; $tmp / 1000" | bc`"${reset} ($3)"
    else
        # If it's SOC just print the result in green
        echo "$2 ${green}$tmp${reset} ($3)"
    fi
}

# Prints the current and design capacity of a battery
function printcap {
    tmp=`cat $bat0/design_capacity`
    design_cap=`echo "scale=2; $tmp / 1000" | bc`
    tmp=`cat $bat0/last_full_capacity`
    last_cap=`echo "scale=2; $tmp / 1000" | bc`

    # Calculate the percentage of the battery's health condition using bc
    condition=`echo "scale=5; ($last_cap / $design_cap) * 100" | bc`

    echo -e "Design capacity: ${green}$design_cap${reset} (Ah)\nLast full charge: ${green}$last_cap${reset} (Ah) (${green}$condition${reset} % of design)."
}


# Prints the voltages of individual battery cells. No input params or return.
# The non-use of functions is ridiculus, I know, but AFAIK bash cannot handle floats a return values, so we have to stick
# to stupid copy-pasting of commands.
function printcells {
    tmp=`cat $bat0/group1_voltage`
    cell1=`echo "scale=2; $tmp / 1000" | bc`
    tmp=`cat $bat0/group1_voltage`
    cell2=`echo "scale=2; $tmp / 1000" | bc`
    tmp=`cat $bat0/group1_voltage`
    cell3=`echo "scale=2; $tmp / 1000" | bc`

    echo "Individual cell voltages: ${green}$cell1 $cell2 $cell3${reset}"
}
########## END OF FUNCTIONS ########### 

# Define some colors
red=`tput setaf 1`
green=`tput setaf 2`
reset=`tput sgr0`

# Battery to monitor
bat0="/sys/devices/platform/smapi/BAT0"

# Main part
echo "Thinkpad Battery Health & Status"

# Check for kernel module tp_smapi. This is an old part of the script, probably unneeded
smapi_loaded=`lsmod |grep tp_smapi`
if [[ "$smapi_loaded" == '' ]] # blank var
then
	gksudo modprobe tp_smapi # load tp_smapi
	smapi_loaded=`lsmod |grep tp_smapi` # recheck if smapi was loaded
	if [[ "$smapi_loaded" == '' ]] #blank var
	then
		echo "Tp_smapi cannot be loaded. Is it installed? Exiting..."
		exit
	fi
fi


# Get some information that will not change much over time
model=`cat $bat0/model`
manufacturer=`cat $bat0/manufacturer`
manufacture_date=`cat $bat0/manufacture_date`
first_use=`cat $bat0/first_use_date`
cycle_count=`cat $bat0/cycle_count`


# Main battery status loop
while :
do
    clear
    # Print title. ${red} etc are for setting color, $(tput bold) is for bold - dah
    echo -e "${red}$(tput bold)== Live battery stats ==${reset}\n"
    myprint remaining_capacity "Current charge:" "Wh"
    myprint voltage "Voltage:" "V"
    printcells

    myprint remaining_percent "SOC:" "%"

    # Is the battery charging/discharging or idle?
    echo -e "State: ${green}`cat $bat0/state`${reset}"

    myprint temperature "Temperature:" "degrees C"
    myprint power_now "Consumption:" "W"

    # Print the capacity and health
    printcap

    echo -e "\n(Wh stands for Watt-hours, Ah for Ampere-hours)\n\n$(tput smul)Further battery info:$(tput rmul)"
    echo -e "You are using a battery with cells made by $manufacturer. Its model is $model and it was manufactured on $manufacture_date. It was first used on $first_use and has been cycled $cycle_count times since."

    sleep "1"
done