Roomba cuts off after a minute or so.

Replace battery, they don’t hold charge as much as new ones, when you leave it charging everyday and use it one or twice a week battery will max out on charges

2nd question,use it now

Most likely your NiCad battery is at the end of it's life and needs replacement. The packs in Roombas are made up of a group of individual cells and what often happens as they age is that a single cell will fail, causing the entire pack to provide less than usable voltage. The Roomba will attempt to operate and then sensing low voltage, it will shut down.

To prevent reduced battery life in the future with your new pack, always keep your Roomba charged as storing a NiCad pack in a discharged state will cause the build up of salts within the pack, damaging the cells.

Replacement is simple and packs are around $40 bucks online, all you need is a small Phillips screwdriver and about 5 minutes.

Lift Roomba off the floor and place it in the center of the room and restart the clean cycle.

If Roomba did not resume cleaning, lift Roomba and turn it over.* Inspect the Side Wheels for dirt or obstructions.

Test the Side Wheels by pushing them in and out and making sure they rotate freely. Place Roomba in the center of the room and restart the clean cycle..

If you're sure the battery contacts are clean and the battery really is charged, then there is faulty circuitry within the Roomba that would have to be repaired or replaced.

Confirm that the battery is inserted with the metal contacts down so they make contact with the spring terminals in the battery compartment.

Visually confirm that the metal contact plates on the battery pack, and the spring terminals in the battery compartment are clean and shiny. If not, wipe with a clean cloth or paper towel, its OK to use a little water or rubbing alcohol on the cloth, if needed, and then dry it.

Visually confirm that the metal contact plates on the Roomba, and the spring terminals on the docking station's home plate are clean and shiny. If not, wipe with a clean cloth or paper towel, its OK to use a little water or rubbing alcohol on the cloth, if needed, and then dry it.

If you have a volmeter, measure the voltage between the contacts on the battery pack If it isn't something in the neighborhood of 14 volts and is 11 volts or less, the battery isn't fully charged.

Reinstall the battery.

For the moment, please connect the power adapter directly to the Roomba rather than the docking station to eliminate one possible faultly connection.

If the battery wasn't fully charged, or you weren't able to test it, try to charge the Roomba and then retest the battery voltage if you can. If the battery voltage was higher immediately after charging, but didn't get to 14 volts, the charger is good, but battery needs to be replaced. If the battery voltage was unchanged after attempting to charge the Roomba, the charging circuitry may be faulty. If there was no light patterns when you tried to charge it, and it was plugged in to a good outlet, then the power adapter or charging circuitry is definitely bad.

If you have no voltmeter and you cleaned the contacts and tried to charge the Roomba and it works, use the Roomba and then recharge using the docking station and see if it was just dirty contacts or it won't charge through the docking station. If it didn't work, you'll need to figure out if its the battery, the charging circuitry in the Roomba, or the power adapter. If there are no lights when you try to charge the Roomba, then Either the power adapter or the Roomba power circuitry is defective, but without a voltmeter you can't find out which one, and there's no way to know if the battery is good or bad, but you know Roomba wasn't trying to charge it. If there are lights when you try to charge the Roomba, then at least you know the power adapter is good. Unfortunately, without being able to test something there's no way to distinguish between a charger that won't deliver a charge to the battery and a battery that won't accept a charge. If you want to take a guess then a bad battery is more common and less expensive to fix.

Hello
You can revive the dead nicd batteries in your tools.
There is a simple guide that can fix all nicd batteries in few minutes, available here.
Thanks

First drain the battery completely and then take out battery and charger and hold power button for 30 seconds and then clean the roomba with compressed air take out all compartments and blow air thoroughly everywhere especially near the wheels where the wheel sensors are. Leave battery to charge for full day and try to run.

It could be the power button itself. If you have a Roomba remote, try using that to power on the robot.

grrrrrr

The best for the battery if (NiMH). Discharge completly, than charge full (charge more even the charger indicates full charge)

Clean every part, maybe a hair slow down the wheels and thats why need more power.

Here some tip from the web:


With proper care, one iRobot Roomba battery can last for hundreds of 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. Your Roomba is powered by a rechargeable nickel metal hydride (NiMH) battery, which lasts the longest when you use it regularly.



Keep the brushes 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. See How to remove and clean Roomba's brushes



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 yourRoomba 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.



Remove the battery when not using your Roomba for a long period of time. If you will not be using your Roomba for more than a few weeks, fully charge the battery, remove it, and store it in a cool, dry place. When you want to use your Roomba again, insert the battery and fully charge it. Leaving your Roomba plugged in for weeks when it is not being used can damage the battery.

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