4 hours ago
(This post was last modified: 1 hour ago by waitingpio.)
PineBuds Pro: Teardown and Battery Replacement
#repair #battery #electronics #Piner
My PineBuds Pro were new old stock. Never used, just sat in a box. When I finally charged them they ran about an hour at low volume with ANC off, which is well under spec.
These buds are repairable and the cells are cheap. The problem is that there's almost no teardown information for them anywhere online, so I wrote this up.
One thing to know before you start: if the buds are old, the cell inside has probably swollen. Mine had. Better to find that out now than halfway through prying the shell apart.
Disclaimer
This is a record of a repair I did on my own PineBuds Pro. I have an electronics background and years of hands-on soldering experience, and this write-up assumes a similar level of skill. It isn't a beginner guide, and it isn't a recommendation that anyone else attempt it.
Lithium cells can vent, catch fire, or explode if punctured, crushed, shorted, or overheated. Opening the buds is irreversible and voids any warranty.
If you try this, you do so entirely at your own risk. I accept no responsibility for any damage, injury, or loss that results.
⚠️ Lithium cells can catch fire if punctured or shorted. Don't pry near the cell, don't let metal touch both terminals, and stop if it gets hot. At your own risk.
Step 1: Open the earbud
![[Image: Pine-Buds-Pro-squeezing-the-earbud-shell.png]](https://i.postimg.cc/wvQmMwtR/Pine-Buds-Pro-squeezing-the-earbud-shell.png)
[pic: squeezing the earbud shell]
There are no screws. The shell is held by internal clips with a little adhesive. The way in is to flex it.
The plastic is soft and has some give. Squeezing the shell deforms it just enough to strain the joint from inside, and the clips release and the glue tears before the plastic takes any damage.
Squeeze firmly near the seam and hold. The seam starts to separate, and you may even see the LED indicator through the gap. Keep the pressure on, work a plastic pry tool into the opening, then run it around the edge to release the remaining clips.
Squeeze in short bursts rather than one long press. Repeated flexing works the clips loose bit by bit, and you get much better control than with steady heavy force.
Step 2: A note on debris and tools
You'll see crumbs or dust as the shell opens. That's the old adhesive breaking up, not the plastic cracking. Nothing to worry about.
Use a plastic pry tool or spudger. Never a metal blade or screwdriver. The shell plastic is good quality and flexes well, but it's soft enough that metal will gouge it.
Use a wide tool too, not a pointed one. A narrow tip puts all the force on one spot, which dents the plastic and can crack the clip underneath. A broad edge spreads that force along the seam so the shell flexes as a whole. A guitar pick works well. Avoid anything sharp.
Step 3: Inside the earbud
![[Image: Pine-Buds-Pro-shell-apart-PCB-visible-sm...-shell.png]](https://i.postimg.cc/RhPJQqLS/Pine-Buds-Pro-shell-apart-PCB-visible-small-black-rubber-cover-loose-in-the-shell.png)
[pic: shell apart, PCB visible, small black rubber cover loose in the shell]
With the shell apart you can see the PCB. It isn't screwed down. It's held by heat-staked plastic posts, where moulded pins have been pushed through the board and their tips melted flat.
How the touch controls work. The inside of the outer cover is lined with aluminium foil. Once assembled, that foil rests against two pogo pins on the PCB, and those pins run to the capacitive sensing pin on the chip. When you touch the outside of the shell (the side facing away from your ear), the capacitance changes and the chip reads it through those pins. That's the whole touch input path for volume, ANC and everything else.
The other four contacts sit on the opposite face, the side against your ear, next to the speaker. Those are the charging and flashing contacts, covered in Step 4.
Don't lose the mic gasket. There's a small black rubber cover sitting in the shell. It belongs over the microphone on the PCB, it isn't attached to anything, and it falls out very easily. Put it somewhere safe as soon as you see it.
Step 4: Remove the PCB
![[Image: Pine-Buds-Pro-PCB-removed-showing-main-c...wiring.png]](https://i.postimg.cc/jqvfrk03/Pine-Buds-Pro-PCB-removed-showing-main-chip-battery-and-wiring.png)
[pic: PCB removed, showing main chip, battery and wiring]
Cut or shave off the melted heads of the plastic posts, then lift the board out. The battery is underneath, hidden by the PCB.
The main chip is a BES2300 (Bestechnic), running from an external 26.000 MHz crystal. A solid, well-supported part.
Six very fine heat-resistant wires run under the board:
An FPC ribbon cable connects to the speaker.
Step 5: The battery
![[Image: Pine-Buds-Pro-battery-lifted-out.png]](https://i.postimg.cc/XYBBdjZx/Pine-Buds-Pro-battery-lifted-out.png)
[pic: battery lifted out]
![[Image: Pine-Buds-Pro-peeling-back-the-foam-tape...-label.png]](https://i.postimg.cc/tCTxRt9X/Pine-Buds-Pro-peeling-back-the-foam-tape-to-reveal-the-label.png)
[pic: peeling back the foam tape to reveal the label]
The battery lifts out once the PCB is clear. It's wrapped in single-sided vibration-damping foam tape. Peel this back to find the label.
Cell: YD 501012, 40 mAh
Measured: 12.8 × 9.6 × 5.5 mm
The part number is the nominal cell size. 501012 means 5.0 mm thick, 10 mm, 12 mm. That's a useful starting point for searching, but it only describes the bare cell. The protection board and the wire joint add to the real dimensions, and different sellers measure differently — some quote the cell alone, some quote the whole assembly. Check the actual measurements in the listing, and where the protection board sits, before you order.
Note the measured thickness is 5.5 mm against a nominal 5.0 mm. You can see in the photo in step 6 that this cell has already swollen a little. That's normal after years in storage and it's almost certainly why the runtime was so bad.
There's no spare room in the shell, so a physically larger cell won't go in. Match these dimensions when you source a replacement.
⚠️ A swollen cell needs care. Don't press it, bend it or puncture it. Lift it out flat, keep it away from anything flammable, and take it to a battery recycling point soon rather than leaving it on the bench.
Step 6: Fitting the new battery
![[Image: Pine-Buds-Pro-disconnecting-one-lead-at-...-ready.png]](https://i.postimg.cc/JhbyYp5K/Pine-Buds-Pro-disconnecting-one-lead-at-a-time-new-cell-ready.png)
[pic: disconnecting one lead at a time, new cell ready]
Disconnect one lead at a time, and insulate each one as soon as it's free. If you cut both leads together with metal cutters you short the cell, because the tool bridges the terminals.
I cut the positive lead first, kept it away from anything metal, taped the end, and only then did the negative.
Choosing a replacement
The cell I used came from a source I trust. It has a protection board built in and a recent manufacturing date. Both of those matter more than the brand name. A cheap unprotected cell sealed inside an earbud isn't worth the risk.
The best match I could find was a 301012, 30 mAh:
Original vs. Replacement
Part: YD 501012 vs. 301012
Capacity: 40 mAh vs. 30 mAh
Nominal size: 5.0 × 10 × 12 mm vs. 3.0 × 10 × 12 mm
Same footprint, 2 mm thinner, 25% less capacity. Less runtime than a factory-fresh bud, but still better than a swollen cell.
The thinner cell leaves about 2 mm of slack in the pocket. I wrapped it with high-temperature-resistant tape until it was a snug fit, which stops it moving around and also insulates it against any short.
Step 7: Soldering
![[Image: Pine-Buds-Pro-new-battery-soldered-to-th...he-PCB.png]](https://i.postimg.cc/qR4NP21Z/Pine-Buds-Pro-new-battery-soldered-to-the-back-side-of-the-PCB.png)
[pic: new battery soldered to the back side of the PCB]
This is the part that needs real soldering skill. The bud and its PCB are small and won't stay put on their own, so I'd strongly suggest a soldering fixture or helping hands. In practice it isn't really optional.
The glue is the main obstacle. The wires and PCB are held with adhesive, which works well against vibration, but under the iron it softens, flows, and covers the pad you're working on. There are also several connectors and wires close by, so there's very little clean space.
What I did instead: I removed the old battery wires from the front of the PCB and soldered the new ones to the back. The joints are through-hole, so the same pads are reachable from behind, and that side is clean and open with no risk of bridging to a neighbouring connector.
Test before you close up. Once the battery is connected the LED should light. The bud doesn't power on by itself, though. The pogo pins go straight to the chip's capacitive sensing pin, so it's your hand on the pins that triggers it. Either way, the LED tells you the joints are good. Check now, not after reassembly.
One thing Pine64 got right: the original wire is ultra-fine, heat-resistant and break-resistant, noticeably better than what came with my replacement cell. Ordinary insulation shrinks back or melts if the iron sits on it a moment too long.
Which gives an option worth considering. You could keep the original wire. Cut the old cell's leads a few millimetres from the battery, cut the new cell's leads short, and splice the two with heat-shrink. The PCB joints never get touched, and the delicate work happens in open air with no glue nearby.
Step 8: Reassembly
![[Image: Pine-Buds-Pro-glue-applied-over-the-batt...minals.png]](https://i.postimg.cc/d30L1wPb/Pine-Buds-Pro-glue-applied-over-the-battery-terminals.png)
[pic: glue applied over the battery terminals]
Before closing anything, check that the battery is seated properly, the wires are clear of any pinch points, and there's nothing that could short.
I put glue over the battery terminals to protect them, and used it to hold the PCB down since the heat-staked posts were cut off in Step 4.
Then, in order:
1. Seat the rubber gasket back onto the microphone. Easy to forget, and a missing gasket means a muffled mic.
2. Check the aluminium foil inside the cover is intact and will sit flat against the pogo pins.
3. Apply glue around the inner edge of the shell.
4. Press the cover back on.
The glue is optional. The internal clips hold the shell closed on their own, so skip it if you'd rather keep the bud easy to open again. When the cover seats properly you'll hear a clear click, and that means it's home.
! Keep glue away from the pogo pins, the aluminium foil, and the clear plastic LED light guide inside the cover. Adhesive on the pins or foil insulates the contact and kills the touch controls. Glue on the light guide clouds it and dims the LED.
Step 9: Clamping and curing
![[Image: Pine-Buds-Pro-earbud-clamped-shut-with-a-clip.png]](https://i.postimg.cc/QtmFhVP0/Pine-Buds-Pro-earbud-clamped-shut-with-a-clip.png)
[pic: earbud clamped shut with a clip]
Clamp the bud shut with a folded paper towel between the clip and the shell, so the pressure is spread out and the plastic doesn't mark. Leave it clamped while the adhesive cures.
I used T7000, the black cellphone repair glue for resealing phone housings after a screen replacement.
Set time 3–6 minutes
Full cure 24–48 hours
Temperature range −35 °C to +90 °C
It's sold as waterproof, flexible, vibration-damping and low-odour once cured.
Don't rush the cure. It's tempting to test after a few minutes, but the bond won't reach full strength for a day or two, and this is the joint holding a lithium cell inside a sealed shell.
Two tips for using it on earbuds. Use it sparingly, because squeeze-out inside the shell is very hard to clean up. And let the buds air out before wearing them, since the solvent smell takes a while to leave a small enclosed space that sits in your ear.
Results
![[Image: Pine-Buds-Pro-with-new-battery-working.png]](https://i.postimg.cc/1Xzfts1x/Pine-Buds-Pro-with-new-battery-working.png)
[pic: PineBuds with new battery, working]
Tested at low volume with ANC off, playing continuously until the earbud announced shutdown.
Runtime went from about 1 hour to roughly 2 hours 12 minutes. I haven't measured it with ANC on.
The touch controls and the microphone both still work after reassembly, so nothing was damaged by the teardown.
Going from 40 mAh to 30 mAh does cost some capacity, and that's the one downside here. But more than doubling the runtime is plenty for me...
A few notes
These are nice to work on.
The shell opens without breaking anything, the wire quality is good, and the board is tidy inside.
Better than I expected, honestly.
Three small things that would make life easier for the next person:
The heat-staked posts are the only step you can't undo. Everything else comes apart and goes back together fine.
A clip or a single small screw would make these properly repairable
as long as whatever replaces the staking still lets the shell give a little, so a swelling cell can push the case open rather than building pressure inside it.
#repair #battery #electronics #Piner
My PineBuds Pro were new old stock. Never used, just sat in a box. When I finally charged them they ran about an hour at low volume with ANC off, which is well under spec.
These buds are repairable and the cells are cheap. The problem is that there's almost no teardown information for them anywhere online, so I wrote this up.
One thing to know before you start: if the buds are old, the cell inside has probably swollen. Mine had. Better to find that out now than halfway through prying the shell apart.
Disclaimer
This is a record of a repair I did on my own PineBuds Pro. I have an electronics background and years of hands-on soldering experience, and this write-up assumes a similar level of skill. It isn't a beginner guide, and it isn't a recommendation that anyone else attempt it.
Lithium cells can vent, catch fire, or explode if punctured, crushed, shorted, or overheated. Opening the buds is irreversible and voids any warranty.
If you try this, you do so entirely at your own risk. I accept no responsibility for any damage, injury, or loss that results.
⚠️ Lithium cells can catch fire if punctured or shorted. Don't pry near the cell, don't let metal touch both terminals, and stop if it gets hot. At your own risk.
Step 1: Open the earbud
[pic: squeezing the earbud shell]
There are no screws. The shell is held by internal clips with a little adhesive. The way in is to flex it.
The plastic is soft and has some give. Squeezing the shell deforms it just enough to strain the joint from inside, and the clips release and the glue tears before the plastic takes any damage.
Squeeze firmly near the seam and hold. The seam starts to separate, and you may even see the LED indicator through the gap. Keep the pressure on, work a plastic pry tool into the opening, then run it around the edge to release the remaining clips.
Squeeze in short bursts rather than one long press. Repeated flexing works the clips loose bit by bit, and you get much better control than with steady heavy force.
Step 2: A note on debris and tools
You'll see crumbs or dust as the shell opens. That's the old adhesive breaking up, not the plastic cracking. Nothing to worry about.
Use a plastic pry tool or spudger. Never a metal blade or screwdriver. The shell plastic is good quality and flexes well, but it's soft enough that metal will gouge it.
Use a wide tool too, not a pointed one. A narrow tip puts all the force on one spot, which dents the plastic and can crack the clip underneath. A broad edge spreads that force along the seam so the shell flexes as a whole. A guitar pick works well. Avoid anything sharp.
Step 3: Inside the earbud
[pic: shell apart, PCB visible, small black rubber cover loose in the shell]
With the shell apart you can see the PCB. It isn't screwed down. It's held by heat-staked plastic posts, where moulded pins have been pushed through the board and their tips melted flat.
How the touch controls work. The inside of the outer cover is lined with aluminium foil. Once assembled, that foil rests against two pogo pins on the PCB, and those pins run to the capacitive sensing pin on the chip. When you touch the outside of the shell (the side facing away from your ear), the capacitance changes and the chip reads it through those pins. That's the whole touch input path for volume, ANC and everything else.
The other four contacts sit on the opposite face, the side against your ear, next to the speaker. Those are the charging and flashing contacts, covered in Step 4.
Don't lose the mic gasket. There's a small black rubber cover sitting in the shell. It belongs over the microphone on the PCB, it isn't attached to anything, and it falls out very easily. Put it somewhere safe as soon as you see it.
Step 4: Remove the PCB
[pic: PCB removed, showing main chip, battery and wiring]
Cut or shave off the melted heads of the plastic posts, then lift the board out. The battery is underneath, hidden by the PCB.
The main chip is a BES2300 (Bestechnic), running from an external 26.000 MHz crystal. A solid, well-supported part.
Six very fine heat-resistant wires run under the board:
- 2 to the battery, B+ and B−
- 4 to the external contact pads: V+ and V− for charging, TX and RX for firmware flashing
An FPC ribbon cable connects to the speaker.
Step 5: The battery
[pic: battery lifted out]
[pic: peeling back the foam tape to reveal the label]
The battery lifts out once the PCB is clear. It's wrapped in single-sided vibration-damping foam tape. Peel this back to find the label.
Cell: YD 501012, 40 mAh
Measured: 12.8 × 9.6 × 5.5 mm
The part number is the nominal cell size. 501012 means 5.0 mm thick, 10 mm, 12 mm. That's a useful starting point for searching, but it only describes the bare cell. The protection board and the wire joint add to the real dimensions, and different sellers measure differently — some quote the cell alone, some quote the whole assembly. Check the actual measurements in the listing, and where the protection board sits, before you order.
Note the measured thickness is 5.5 mm against a nominal 5.0 mm. You can see in the photo in step 6 that this cell has already swollen a little. That's normal after years in storage and it's almost certainly why the runtime was so bad.
There's no spare room in the shell, so a physically larger cell won't go in. Match these dimensions when you source a replacement.
⚠️ A swollen cell needs care. Don't press it, bend it or puncture it. Lift it out flat, keep it away from anything flammable, and take it to a battery recycling point soon rather than leaving it on the bench.
Step 6: Fitting the new battery
[pic: disconnecting one lead at a time, new cell ready]
Disconnect one lead at a time, and insulate each one as soon as it's free. If you cut both leads together with metal cutters you short the cell, because the tool bridges the terminals.
I cut the positive lead first, kept it away from anything metal, taped the end, and only then did the negative.
Choosing a replacement
The cell I used came from a source I trust. It has a protection board built in and a recent manufacturing date. Both of those matter more than the brand name. A cheap unprotected cell sealed inside an earbud isn't worth the risk.
The best match I could find was a 301012, 30 mAh:
Original vs. Replacement
Part: YD 501012 vs. 301012
Capacity: 40 mAh vs. 30 mAh
Nominal size: 5.0 × 10 × 12 mm vs. 3.0 × 10 × 12 mm
Same footprint, 2 mm thinner, 25% less capacity. Less runtime than a factory-fresh bud, but still better than a swollen cell.
The thinner cell leaves about 2 mm of slack in the pocket. I wrapped it with high-temperature-resistant tape until it was a snug fit, which stops it moving around and also insulates it against any short.
Step 7: Soldering
[pic: new battery soldered to the back side of the PCB]
This is the part that needs real soldering skill. The bud and its PCB are small and won't stay put on their own, so I'd strongly suggest a soldering fixture or helping hands. In practice it isn't really optional.
The glue is the main obstacle. The wires and PCB are held with adhesive, which works well against vibration, but under the iron it softens, flows, and covers the pad you're working on. There are also several connectors and wires close by, so there's very little clean space.
What I did instead: I removed the old battery wires from the front of the PCB and soldered the new ones to the back. The joints are through-hole, so the same pads are reachable from behind, and that side is clean and open with no risk of bridging to a neighbouring connector.
Test before you close up. Once the battery is connected the LED should light. The bud doesn't power on by itself, though. The pogo pins go straight to the chip's capacitive sensing pin, so it's your hand on the pins that triggers it. Either way, the LED tells you the joints are good. Check now, not after reassembly.
One thing Pine64 got right: the original wire is ultra-fine, heat-resistant and break-resistant, noticeably better than what came with my replacement cell. Ordinary insulation shrinks back or melts if the iron sits on it a moment too long.
Which gives an option worth considering. You could keep the original wire. Cut the old cell's leads a few millimetres from the battery, cut the new cell's leads short, and splice the two with heat-shrink. The PCB joints never get touched, and the delicate work happens in open air with no glue nearby.
Step 8: Reassembly
[pic: glue applied over the battery terminals]
Before closing anything, check that the battery is seated properly, the wires are clear of any pinch points, and there's nothing that could short.
I put glue over the battery terminals to protect them, and used it to hold the PCB down since the heat-staked posts were cut off in Step 4.
Then, in order:
1. Seat the rubber gasket back onto the microphone. Easy to forget, and a missing gasket means a muffled mic.
2. Check the aluminium foil inside the cover is intact and will sit flat against the pogo pins.
3. Apply glue around the inner edge of the shell.
4. Press the cover back on.
The glue is optional. The internal clips hold the shell closed on their own, so skip it if you'd rather keep the bud easy to open again. When the cover seats properly you'll hear a clear click, and that means it's home.
! Keep glue away from the pogo pins, the aluminium foil, and the clear plastic LED light guide inside the cover. Adhesive on the pins or foil insulates the contact and kills the touch controls. Glue on the light guide clouds it and dims the LED.
Step 9: Clamping and curing
[pic: earbud clamped shut with a clip]
Clamp the bud shut with a folded paper towel between the clip and the shell, so the pressure is spread out and the plastic doesn't mark. Leave it clamped while the adhesive cures.
I used T7000, the black cellphone repair glue for resealing phone housings after a screen replacement.
Set time 3–6 minutes
Full cure 24–48 hours
Temperature range −35 °C to +90 °C
It's sold as waterproof, flexible, vibration-damping and low-odour once cured.
Don't rush the cure. It's tempting to test after a few minutes, but the bond won't reach full strength for a day or two, and this is the joint holding a lithium cell inside a sealed shell.
Two tips for using it on earbuds. Use it sparingly, because squeeze-out inside the shell is very hard to clean up. And let the buds air out before wearing them, since the solvent smell takes a while to leave a small enclosed space that sits in your ear.
Results
[pic: PineBuds with new battery, working]
Tested at low volume with ANC off, playing continuously until the earbud announced shutdown.
Runtime went from about 1 hour to roughly 2 hours 12 minutes. I haven't measured it with ANC on.
The touch controls and the microphone both still work after reassembly, so nothing was damaged by the teardown.
Going from 40 mAh to 30 mAh does cost some capacity, and that's the one downside here. But more than doubling the runtime is plenty for me...
A few notes
These are nice to work on.
The shell opens without breaking anything, the wire quality is good, and the board is tidy inside.
Better than I expected, honestly.
Three small things that would make life easier for the next person:
The heat-staked posts are the only step you can't undo. Everything else comes apart and goes back together fine.
A clip or a single small screw would make these properly repairable
as long as whatever replaces the staking still lets the shell give a little, so a swelling cell can push the case open rather than building pressure inside it.
