Best Replacement Battery For iRobot Roomba 891

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While having choices can be a good thing there is such a thing as too many, especially when it comes to choosing a battery replacement for your iRobot Roomba 891 that isn’t a knock-off. We know this problem all too well because we have been here ourselves.

However, after an extensive amount of research and testing, we have found the best available replacement battery on the market for your Roomba 891.

Best Replacement Battery For iRobot Roomba 891

iRobot Roomba 891 Replacement Battery
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iRobot Roomba 891 Replacement Battery
iRobot Roomba 891 Replacement Battery

A Guide to Buying A Replacement Battery for Roomba 891

You either want to replace your Roomba 891 battery with a Lithium-ion or Nickel Metal Hydride battery.

The main difference between these two batteries is the material that is used to store the battery’s power. Lithium-ion batteries are carbon and highly-reactive lithium-based, which is capable of storing lots of energy.

Meanwhile, the Nickel-metal hydride batteries work by using hydrogen to store the energy as the nickel and another metal, such as titanium, keeps the hydrogen ions contained.

There are other obvious differences between these two batteries to consider, including the following:

  • Cost

Nickel metal hydride batteries are the less expensive choice.

  • Weight

Nickel metal hydride batteries are larger and heavier than Lithium-ion batteries.

  • Power

Both of these batteries can actually hold around the same amount of power, however, the Lithium-ion cells can be charged and discharged quicker.

  • Durability

Both of these batteries are durable, however, Lithium-ion batteries just don’t last as long when it comes to extremely hot and cold climates. This is something that Lithium-ion battery manufacturers are currently working on improving

  • Battery Capacity: mAh

mAh means milliamp Hour and is a unit of measurement for electric power over time. This unit is commonly used to measure the life capacity of a battery.

In short, the more mAh a battery has, the more energy it can store, leading to longer battery life.

This unit can be used to give you an idea of how long a device will last with the constant or average power drawing rate.

For example, a battery with 3000 mAh can power a device that draws 100 mA for 30 hours, while a device drawing 200mA would only last about 15 hours in comparison.

Replacing Your Roomba 891 Battery

If you have never replaced the battery before and are hesitant about doing it yourself, follow the guide below for easy battery removal and replacement.

  • Turn the device upside down and use a screwdriver to remove the side brush.
  • Loosen the four screws that hold the bottom cover on, then remove it.
  • Remove the battery inside.
  • Place the new battery into the Roomba 891 with the manufacturer’s logo facing up.
  • Replace the cover and all four screws, then tighten them.
  • Replace the side brush and tighten its screw to finish the process.

How to Extend the Life Of Your Roomba 891 Battery

It’s important to perform simple maintenance steps to get the most out of your batteries and to enjoy effortless cleaning. Follow the provided maintenance tips below to enjoy a longer battery life for your Roomba 891.

  • Clean the Brushes

When the device cleans, it picks up hair, dust, fur, and more. With all of these things caught in the brushes, it makes it more difficult to clean due to the brushes being heavy and thus sucking the life from your battery much quicker. Clean all of the brushes at least once a week to prevent this.

  • Keep The Battery Charged

Nickel-based batteries need to be charged whenever the device isn’t in use to keep its life up.

  • Use Up the Charge in One Cleaning

By running the device until the battery dies and then charging it to full capacity, you will extend the life of the battery.

  • Store the Device in A Cool Place

Storing your electronic devices in a cool spot is just smart thinking, as electronic devices tend to like the cold, especially when it comes to batteries.

The cold preserves the life of the device and its battery, so don’t place near a radiator or any other electronics that produce heat.

  • Activate Vacation Mode

The Roomba 891 has a vacation mode that can be used to ensure the battery remains charged when the device isn’t in use.

To turn on vacation mode, charge the accumulator, then remove it and store it in a safe place separate from the unit.