Fixing a Phone with a Non-Repalacable Battery

Disclaimer: this is not the neatest and prettiest thing I've ever coded up. I feel like I'm coding sloppy, making something raw and unfinished, but that's the perfectionist who went to code camp in me talking. I intentionally wanted the photos to be very big and kept the font plain for readablity. If I am repairing things and looking at their photos and videos really big versions of pics and hardcore closeups are incredibly helpful. This is essentially like a blog post of how I handled an LG K51 that was handed to me and in need of help.

I was handed a phone that had been giving issues. The very first thing did was I listened and asked questions. The battery has had times of draining quickly. Other times, it has been behaving normally. I had said to check to make sure your apps, when not in use, are closed out. Even after following that advice for about a month, the battery life was inconsistent and not looking so great. So, I said, let's change out your battery.

The phone put in my hands was an LG K51 purchased in 2020. I hopped online and saw other people fixing this model to get information about how to make an appropriate repair. So I put on some tuneage and got to work.

The very first thing I had to do was turn off the phone and get the SIM card tray out! After that, I could get down to business. I had to get the back off. Getting the back off was a complete struggle bus adventure at first. The back had never come off, and the factory had used adhesive to seal it shut. It was frustrating, but I was going to solve it. Eventually, I saw someone applying a bit of heat with a heat gun. I said I have a hair dryer, and that runs hot. I ran the hair dryer around the edges and used one of my bass picks and a small flathead screwdriver to carefully pry the edges cleanly off. The key word in that sentence is careful.

I knew to be careful because, from watching all the repairs, I knew that there was a fingerprint sensor. The fingerprint sensor ran from the inside cover and connected to the motherboard. So, I had to work delicately to pop the cover off. I did that and temporarily disconnected the sensor from the motherboard. It was connected with a ribbon cable, and I popped it up with my bass pick.

From there, I had to remove the metal antenna. It's the big metal plate in the pic.

It was screwed down with tiny screws that I placed in a coffee mug that I was using as a parts tray. When I got the tiny screws removed with my tiny Phillips head screwdriver, I had to use a bass pick again to pop the antenna up to get it free.

I was at the motherboard where the battery was attached. So, the bass pick was again used to pop up how the battery was attached to the board.

I put the batteries side by side. I wanted to double check to see I had the right battery at this stage.

Once again, I had to have fun getting adhesive to break free. The battery was again stuck down with adhesive. I then busted out the rubbing alcohol. I poured it into a bathroom cup and grabbed the Q tips.

I dipped the q tips in the alcohol and liberally ran it along the edges of the battery.

I gave it a few minutes to work its magic and break down more adhesive. Then, I took my bass pick and ran it around the edges of my battery. I did the Q-tip application of alcohol again and kept rocking the bass pick until I could feel it hitting metal.

From that point, I took a large, wide, flat head and my bass pick to pry up the battery from the bottom of the battery cavity. See the adhesive on the back of the battery in the following picture.

Success!!! It broke free neatly just by being persistent with the alcohol and bass pick. I removed the old battery and snapped in an OEM battery from eBay. Then, I had to snap on the part that connects to the board.

Objective complete! Then I had to reassemble, put the SIM card tray back in, and turn it back on.

Success!!! It booted up. So far, the new battery is behaving and holding a charge.

Hopefully this has contributed to knowledge and repairs on this model of phone. I want to make a point to please do a parts check on your battery. I originally ordered the wrong battery as I thought the user had a slightly different model. That was my bad. There are a few versions of LG K51 so double check your parts. I double check my parts on any project, but I check extra careful with mobile phones as those subtle differences are super important so the repair is done correctly.