How To Replace The Battery in a Remington PG-520 Beard Trimmer

Hardware:

• Remington Model PG-520 Beard Trimmer

Tools Needed:

• Pocket Knife or Pry Tool (I used one like the metal one found in this set of pry tools)
• Phillips-head screwdriver, like those in this Precision Screwdriver Set
• Soldering Iron (I used a high-powered “gun” type like this)
• Helping Hand Magnifier Tool

Parts Needed:

• AA NiCd Cell Battery with Tabs 1000mAh (replacement for stock BYD D-AA600mAh 1.2V M23)
• Solder
• Desoldering Wick
• Gorilla Super Glue
  (if you break the case like I did when disassembling the trimmer–I love this brand of glue because the bottle seals up every time and it doesn’t dry up like the old fashioned type–I’ve had this bottle for over a year)

Twist the trimmer head counter-clockwise about a quarter inch to unlatch it and then pull it off

Here’s what you’ll have when you get it off:

Trimmer head removed

Step 2: Remove the rubber grip.  This piece is plastic covered in rubber and wraps about 300 degrees around the trimmer body:

Rubber grip piece

I used a pry tool I received with an iPhone display I purchased to fix a friends iPhone 4S.  Important note: the rubber grip piece has a tab that tucks under on the trimmer end so don’t pry on that end–pry on the sides.  Here is where you need to pry on both sides:

Prying off the rubber grip

Here’s what it looks like when it starts to pry up:

The rubber grip is popping off

And finally off:

Rubber grip removed (see the tab on the top)

Step 3: Pry off the power button slider.

There’s a hidden screw under there that we must remove.  It snaps straight down onto the body of the trimmer.  Pry it off like this:

Prying up the power slider

Here’s the power button slider removed.  Note that the two outside tabs are what snaps it in place and the middle tab is what sits down into a white plastic piece that runs to the switch.

Power button slider removed

Step 4: Remove the screw that was hidden under the power slider button.

There it is:

Screw location under power slider button

Step 5: Pry off the center plastic panel.

Start at the end by where the power plug goes:

Prying off the center silver plastic panel–start on the end

It will begin to come up:

Prying off the center silver panel

The sliver piece loops around the other end so be careful when removing it.  And here’s the piece removed:

Silver plastic panel removed

Some of the black body broke off when I was taking off the silver panel.  I’m not sure what caused that but you can see it here (and it wasn’t glued to the silver piece):

The edge of the black body broke off

Step 6: Pry the two halves of the body apart.

There are two large tabs under where the rubber grip was that need to be unlatched.  The one on the trimmer end is marked in the picture below.  There is one on each side and you should unlatch them first.

Separating the halves, part 1

Once you have the first two tabs unlatched you can unlatch the next to as shown below:

Prying the second tab free

Once you get the four main tabs freed this is what you’ll see:

The two halves freed, left side

The two halves freed, right side

Two halves separated

Step 7: Remove the screw securing the circuit board.

Lift out the battery as seen below.  It isn’t secured in place and simply fits down into a trough created by the plastic body.

Circuit board screw location

Once you remove the screw you can take the motor, circuit board, battery and power plug out of the trimmer body:

The trimmer insides removed

Note the battery connections on the circuit board are labeled B+ and B- for the positive (+) and negative (-) terminals of the battery, along with the red wire standing for positive which is common:

Add caption

Step 8: Remove the old battery.

Now if you purchased the replacement battery I have linked at the top of this page then you should unsolder the battery wires from the tabs on the old/original battery and solder the new battery to the original wires.  Those wires pass through a hole in the tab so you’ll need to heat the solder up and then pull them out.  I actually used half of a NiCad battery pack I had on hand and separated the two batteries:

NiCad 2-AA battery pack

I pealed off the plastic shrink wrap and then separated the two batteries that were glued together (I had to use a pocket knife because they were glued together):

Batteries separated

I then cut the tab that connected the two cells.  I wanted to use the existing tab to solder the old lead back on so if you do it this way be careful not to pull the spot welds off the end of the battery.

Cutting the metal tab in half

I used my “extra set of hands” to hold the battery while I was soldering (clipped to a piece of duct tape I put on the battery to give it something to grab onto):

Put some solder on the metal tab to prep it for soldering the wire on it

To unsolder the wires from the circuit board, heat up the solder joint while pulling on the wire:

Old battery unsoldered

Here’s the battery details:

Battery details: BYD D-AA600mAh 1.2V M23

The original battery is 600mAh, the two pack I am using is 2.4V and 500mAh.  At 1.2V, each cell will also be 500mAh, so this battery will have slightly lower capacity (20% lower) than the original but it’s what I had on hand so that’s what I went with.  It’s nice when you can repair something with parts on hand 🙂

I then removed the solder from the battery connections on the circuit board using solder wick.  To do this simply press the solder wick against the solder with a hot soldering iron tip and when the solder begins to melt it will be drawn up into the solder wick.

Solder removed from the negative connection

Solder removed from the positive connection

Step 9: Install the new battery.

Depending on if you are using the battery I link to in at the top or if you are doing it the way I’m doing it with a scavenged battery, your steps will vary.  In my case I first soldered the old negative wire onto the new battery (on the end that had the tab).  I used the positive wire on the other end that was already connected to the battery:

Old wire soldered onto new battery

I then cleaned a little of the insulation off the end of the positive wire.  I then lightly tinned the bare wire.  Tinning is melting solder into the wire, which aids in making a quick solder connection.  If you put too much solder on it, it will not go through the hole on the circuit board (which was the case for me the first time I tried it):

Here I’m about to “tin” the end of the positive wire on my new battery

Insert the new wires into the correct polarity of hole in the circuit board and solder in place.  If you are using the battery I linked in the description you would not be doing this but you would be soldering the old/existing wires to the new battery.

New Battery soldered in place

Step 10: Reinstall the “insides” of the trimmer.

Line up the LED with the hole in the case and insert the power plug into the slot made to hold it in the case, and then nestle the battery down into the two u-shaped slots in the case designed to hold it:

Time to install the guts

Location of parts

Once you have everything lined up, reinstall the screw into the circuit board.

Reinstalling the circuit board screw

Because of the proximity of the negative end of the battery to the power plug, there originally was a piece of tape over the end of the battery.  I transferred this over to the new battery:

Tape applied to new battery

Step 11: Seat the battery in the case.

There are two trough-shaped plastic tabs that stick up that the battery sits down on.  Once you have the battery seated, transfer the foam stickers onto the top of the new battery as seen below:

Battery re-seated into case and the foam pads transferred over

Step 12: Partially put the second half of the case onto the trimmer.

Don’t snap it together though because we need to install a little round plastic piece on the end that surrounds the motor shaft and is what the trimmer head locks into.  This is what you should have:

Case partially re-assembled but not snapped together on the trimmer head end

Step 13: Reinstall the black round plastic end that the cutter head assembly snaps into.

I wasn’t sure which way to orient this piece at first because part of the black case had broken off when I disassembled the trimmer so I installed the trimmer head and compared it to the original pictures to figure it out.

Orientation of round plastic part that slides over the shaft

Step 14:  Snap the case together.

Pay attention to the seams to make sure that the correct edge is tucked under the other edge.  This is what you should have:

Case snapped together

Step 15: Glue the case, if necessary.

Somehow the top edge of the black case broke off when I disassembled this trimmer so once I had the case all snapped together I super glued the two pieces back on:

Super gluing the two pieces back on the edge (and these pieces help hold the round part on the end)

I used a scavenged case fan to help the glue dry faster.  Read about how to power scavenged fans on my post here: How to Power a Scavenged Fan with a Used Wall Plug

Drying the glue with a scavenged case fan

Here’s another good reason to have an Extra Set of Hands Magnifier Tool, to hold your fan for you:

Holding the fan with my extra set of hands

Step 16: Reinstall the silver center panel.

It loops over the end of the trimer and then snaps into place.  Here I’m about to snap it down into place:

Reinstalling the silver center panel

After you snap the silver panel down, reinstall the screw:

Reinstalling the center silver panel screw

Step 17: Reinstall the power slider button.

First you’ll want to line up the white plastic piece that the power slider button sits down into.  When I got to this point the rectangular slot in the white inner plastic piece was hidden under the case.  I used a straightened paperclip to move it into view:

Rectangular slot in white plastic part is fully in view (in off position now)

The tab that sticks out on the back of the switch (circled below) goes in the hole seen above.

Align the tab with the slot and snap it straight down:

Switch reinstalled

Step 18: Snap the rubber wrap-around grip back on.

First tuck in the tab on the end that is closest to the power adapter like this:

Reinstalling the rubber wrap-around grip

When you get it fully snapped into place the seams should be tight.  It will be tight apart from any damage you did when prying them apart and I had to take it apart a couple times because I was learning as I went and made some mistakes that I have saved you from making:

I caused a little damage when I took it apart but not too bad

Step 19: Reinstall the trimmer head assembly.

Insert it straight on and then turn it slightly to lock it in place.

Trimmer Reassembled

Step 20: Charge it up.

Now you’ve extended the life of your charger and saved some money!

The amber light indicates the charger is connected to power and is charging