New LiftMaster 485LM Battery Backup for Garage Door Openers 3840 3850 8360 8550

Since my garage door manual did not specify a battery replacement, I was nervous this battery wouldn’t work. But with the product description and other buyer’s reviews, I picked this battery and it worked perfectly. The instructions were good and several buyers gave helpful tips on installation. That annoying beeping is now gone. Nice!

Great replacement

Good value for the money. Seems to work well. Time will tell. Fits right in, connect the terminals and back in business.

I purchased this battery from the Amazon seller "AAA Security Depot USA". There were several listing for this same item by various sellers, all to be fulfilled by Amazon, and many with prices that were nearly identical. In reading the reviews, which Amazon seems to lump together for all sellers, I noticed that some buyers complained that the batteries they had received had older production dates than they'd prefer. I specifically chose the seller AAA Security Depot USA because one reviewer said the battery that he purchased from this seller was very fresh. That's exactly what I was looking for. My previous battery would no longer hold a charge. It had been installed brand new into a new Liftmaster Garage Door opener that I purchased in Nov. 2018. That battery had a production date of 07/2018, so it lasted installed and in use for exactly 6 years before it started beeping that it needed replacement. This new replacement battery I ordered from AAA Security Depot USA arrived the first week of March 2025, and had a production date stamped on it of 10/30/24. Just like the original, it was sold within 4 months of it's production date, so I had no worry that it had been sitting on a warehouse shelf for an extended period. I had looked all over the web for the best price, including on the Liftmaster website itself. The price offered by this seller was the second lowest I could find, and less in total than even what Liftmaster offered because Amazon had free shipping, and the Amazon fulfillment/shipping time was quicker! This new battery arrived FRESH to my doorstep in just 2 days. It doesn't get easier than that!

great product

Easy to install

Just what was needed for a replacement! Worked perfect!!!

The constant low backup battery warning beeping from my Lift Master Model 8550W-7 with Wi-Fi has stopped! This battery is the perfect replacement for the original battery that lasted seven years. And, if you are concerned, it is very easy to replace. You do need a small ladder to reach the garage door opener and a Phillips head screw driver (I also used a pair of pliers). While standing on your ladder, unplug the unit, open the light cover (mine was on the right side of the unit as you face the garage door), unscrew the screw holding the battery compartment cover (if you drop the screw -- no worries -- it falls into the open light cover), remove the red and black wire connectors from the battery terminals (I had to use a pair of needle nose pliers to wiggle the connectors to get them off), slide the old battery out of the compartment, slip in the new battery, reconnect the wires to the red and black terminals (make sure you get the correct color wire on the same colored terminal), replace the cover with the screw, close the light cover, plug the unit back in and you are done. Took me 10 minutes at most. Best of all, the beeping did not return. On the other side of the unit, if you open the other light cover, you will see a green light -- mine was flashing which I think means that the new battery is charging. Anyway, glad I purchased the battery and did not have to pay a garage door technician to install it.