With proper care, one iRobot Roomba battery can last for many cleaning cycles before you need to replace it. Here are some things you can do to extend Roomba's battery life and keep Roomba cleaning at peak performance:

• Use your Roomba frequently. The batteries last the longest when charged more frequently.
  


• Keep the brushes and brush bearings clean. If the brushes and brush axles get clogged with hair and other debris, your Roomba will strain to spin them, using more battery power than normal. In extreme cases, the battery can even be damaged.

• Keep your Roomba plugged in when not in use. If you have a Home Base™, keep your Roomba docked in the Home Base and plugged into the charging brick. If you don’t have a Home Base, keep your Roomba plugged into the APS Fast Charger.

• Make sure you are charging your Roomba correctly. When your Roomba is plugged in correctly, the solid green light should be illuminated on the charger or on the Home Base.

• Plug your Roomba in as soon as possible after using Max Mode. Leaving your Roomba unplugged for more than 24 hours can damage the battery.

• Place your Roomba and the Home Base on a smooth, hard surface when your Roomba is plugged in. Make sure your Roomba and the Home Base have plenty of space for ventilation. Do not charge your Roomba on a carpet or rug.

• Charge and store your Roomba in a cool, dry place. Keep your Roomba out of direct sunlight and away from sources of heat such as windows, radiators, heating vents, and large appliances.

• Long-term storage – A battery left in a Roomba will slowly run down if it is not kept charging since it draws a small current while off. Allowing the battery to enter a deep discharge state can be harmful to it. If you are not using the robot for a few weeks and your battery is yellow, it is best to fully charge the battery and then remove it from the Roomba and store it separately. If your battery is black or blue, use the Roomba first, then store it.

1. Press and hold the two buttons above and below the CLEAN button simultaneously for 10 seconds to reset Roomba.
2. Charge Roomba until the CLEAN light turns green.
3. Allow Roomba to run until it plays the 4-tone "dead battery" song indicating that the battery has been fully discharged. 
   • If you use a Home Base, unplug it so Roomba does not attempt to dock when its battery is low.
   • If you have a DOCK button, use this to fully discharge your battery.
   • If you do not have a DOCK button, you may need to run several CLEAN cycles to discharge the battery.
4. Be sure to recharge your Roomba as soon as possible after the battery has been fully discharged.

You can also purchase a second battery or replacement battery online at the iRobot Store.