Method for operation of device using battery state of health

A device, comprising:

• a battery;
• and
• a controller that is configured to execute instructions for:
• determining a first resistance value for the battery during a first power cycle of the battery and at a first state of charge value for the battery,
• determining a second resistance value for the battery during a second power cycle of the battery, the second power cycle being after the first power cycle, and at the first state of charge value for the battery,
• determining that a first difference equal to the first resistance value subtracted from the second resistance value is less than a first predetermined threshold value, and
• electrically isolating the battery.

A method comprising

• determining, using a controller in a device, a first resistance value for a battery in the device during a first power cycle of the battery and at a first state of charge value for the battery,
• determining, using the controller, a second resistance value for the battery during a second power cycle of the battery, the second power cycle being after the first power cycle, and the first state of charge value for the battery,
• determining, using the controller, that a first difference equal to the first resistance value subtracted from the second resistance value is less a first predetermined resistance difference threshold value, and
• electrically isolating the battery.