Galaxy S9 Plus Battery Replacement: Cost & Guide
A Galaxy S9 Plus battery replacement costs roughly $12 to $28 for the part on a DIY swap, or about $45 to $85 at a repair shop. Released in March 2018, the S9+ is now one of the oldest flagships people still keep in daily rotation — which means almost every surviving unit is running on a battery well past its designed lifespan. Swapping the 3500mAh cell is very much a DIY job, and it is the cheapest way by far to make an aging S9+ feel usable again.
This guide covers how to gauge the old cell, what a replacement really costs, the exact battery to buy, and how to do the swap without cracking glass.
An eight-year-old battery is the real problem
The Galaxy S9 Plus is pushing eight years old. Lithium-ion cells are rated for around 500 full charge cycles before capacity drops to about 80%, and an S9+ that has been charged daily since 2018 has burned through that budget many times over. A pack that started at 3500mAh may now deliver well under 2500mAh of usable charge — sometimes far less.
That age is the whole story behind the symptoms owners describe. No amount of closing background apps or dimming the screen brings back capacity that the chemistry has permanently lost. The only real fix is a new cell.
How to check your Galaxy S9 Plus battery health
Modern Samsung phones expose a battery-health percentage at Settings → Battery and device care → Battery → Diagnostics → Battery health under One UI 5 or newer. The S9+ never got there — its software life ended at Android 10 / One UI 2.5, so there is no native health percentage anywhere in its menus.
The honest way to estimate capacity is a free tool like AccuBattery. It measures the current flowing into the pack across your normal charges and calculates real capacity from it. Do not act on the first number — let it record three or four full cycles first. On a phone this old, do not be surprised if it reports 2000mAh or less against the 3500mAh original rating; that is exactly why runtime collapsed.
You can also open Samsung Members → Get help → Interactive checks → Battery for a quick good-or-bad status, though it will not give you a percentage.
Signs your Galaxy S9 Plus battery is failing
If your Galaxy S9 Plus battery is draining fast, look for the classic end-of-life pattern rather than one bad day:
- The phone lasts only a few hours off the charger.
- It shuts down suddenly at 20-40%, especially in cold weather.
- It runs warm and charges slowly, or refuses to hold a charge overnight.
- The curved back glass or the display is lifting at an edge.
Swelling safety note: that last symptom is the urgent one. A battery this old is a prime candidate for swelling. If the S9+'s glass back is bulging, the screen is pushing up, or the phone rocks on a flat table, stop charging it immediately, keep it away from heat, and never puncture or bend it. A swollen lithium pouch can rupture or ignite, and on the S9+'s curved Infinity Display it can crack the screen from the inside. Replace it right away.
Galaxy S9 Plus battery replacement cost in 2026
The S9+ is long out of Samsung's standard support window, so official service is limited and expensive where offered at all. A local shop is the easy middle path, and DIY is by far the cheapest. Here is the 2026 picture:
| Option | What you get | 2026 price |
|---|---|---|
| Manufacturer / authorized service | Genuine cell + labor, rarely offered this old | $55-95 (if available) |
| Local repair shop | Part + labor, same-day | $45-85 |
| DIY with a quality replacement battery | The cell, adhesive, and tools | $12-28 + tools |
A "galaxy s9 plus battery replacement near me" search will mostly turn up shops in the $45-85 range, where labor is most of the bill. Since the phone is old enough that you are unlikely to worry about voiding anything, DIY makes a lot of sense — you keep the part cost and skip the labor.
The exact replacement battery for the Galaxy S9 Plus
The Galaxy S9 Plus uses a 3500mAh lithium-polymer cell, Samsung part number EB-BG965ABE. It fits every S9+ variant — sold as SM-G965, SM-G9650, SM-G965F, SM-G965N, SM-G965U, and SM-G965U1. Note that this is the Plus-specific cell; the standard S9 uses a smaller 3000mAh pack (EB-BG960ABE), which will not fit the larger S9+ chassis. Match the part number and you are safe.
Shopping for a galaxy s9 plus oem battery, confirm the EB-BG965ABE part number, the 3.85V / 3500mAh rating, and pick a quality cell over an unbranded no-name pack — a fresh cell in an eight-year-old phone is only worth it if the cell itself is good. You will find the correct part on our Galaxy S9 Plus replacement battery page, and the wider range on our replacement batteries collection. We ship fast across the US, retail or wholesale for repair pros ordering in bulk.
How to replace a Galaxy S9 Plus battery yourself
Honest difficulty rating: moderate to hard, about 6 out of 10. Like the rest of that Samsung generation, the S9+ opens from the back through glued curved glass, and the battery sits under firm adhesive. It is well within reach of a careful first-timer, but the curved glass punishes impatience — heat everything thoroughly and pry slowly. Budget 45-75 minutes.
Overview of the job:
- Power down and heat the back. Warm the rear glass with a heat pad or hair dryer until the perimeter adhesive softens, then work a suction cup and thin picks around the curved edge to lift the panel. Watch for cables near the edges.
- Remove the brackets. Unscrew the plastic charging-coil assembly and the board shields covering the battery connector.
- Disconnect the battery connector first, before doing anything else inside.
- Free the old cell. Apply a few drops of isopropyl alcohol or use adhesive pull-strips, then lift the pack out flat and evenly. Never fold or puncture a battery.
- Install the new 3500mAh cell, reconnect, reassemble the brackets, and reseal the back glass with fresh adhesive.
Have on hand a heat source, a suction cup, plastic opening picks/spudgers, a Phillips #00 driver, tweezers, replacement adhesive, and isopropyl alcohol, plus a teardown reference. For steps on other phones, see our phone battery replacement by model guide.
After the swap: calibrate the new cell
Samsung phones do not lock out third-party batteries the way an iPhone flags an "unknown part," so the S9+ will simply power on and work. You may see an occasional generic notice that a non-original component was detected — it is purely informational and does not disable anything.
To get an accurate gauge on a fresh cell, run one calibration cycle: charge to 100%, leave it plugged in an extra 30 minutes, then use the phone until it powers off on its own, and finally charge back to 100% without unplugging. This resyncs the software fuel gauge to the new battery's true capacity so the percentage stops jumping. One clean cycle is enough.
Repair vs. upgrade: is an eight-year-old S9 Plus worth saving?
Even at eight years old, the S9+ still handles messaging, calls, browsing, and everyday photos fine — the processor and that lovely curved AMOLED did not wear out. The battery did. A $12-28 cell versus $400-plus for a new phone is a lopsided comparison, and if the S9+ still does what you need, the battery is the smart spend.
It is the greener choice as well. Every new smartphone represents roughly 60kg of CO2 and a fresh draw on mined materials. Keeping a device you already own alive with a new cell is the heart of "repair, don't replace," and it keeps a perfectly functional phone out of the e-waste pile for a couple more years. For an S9+ that is otherwise sound, a battery beats a landfill every time.
FAQ
How much does a Galaxy S9 Plus battery replacement cost?
About $12-28 for the battery on a DIY swap, or $45-85 at a repair shop where labor is most of the cost. Manufacturer service is rarely offered on a phone this old, but where available runs $55-95.
How do I replace a Galaxy S9 Plus battery?
Power down, heat the curved back glass to release the adhesive, lift the panel with a suction cup, remove the internal brackets, disconnect the battery connector first, free the old 3500mAh cell with isopropyl alcohol, install the new EB-BG965ABE battery, and reseal with fresh adhesive. Plan on 45-75 minutes.
Why is my Galaxy S9 Plus battery draining fast?
After roughly eight years and many hundreds of charge cycles, the original 3500mAh cell has lost much of its capacity. This is normal age-related degradation, and only a new battery restores runtime.
Does the Galaxy S9 Plus show battery health in settings?
No. The S9+ ended its software life at Android 10 / One UI 2.5 and never received Samsung's native battery-health percentage, which arrived in One UI 5. Use a free app like AccuBattery and let it run several cycles before trusting the estimate.
What is the correct OEM battery for the Galaxy S9 Plus?
The genuine part is the 3500mAh EB-BG965ABE, which fits all SM-G965 variants. The standard S9 uses a smaller 3000mAh EB-BG960ABE cell that will not fit the larger S9+.
Is a swollen Galaxy S9 Plus battery dangerous?
Yes. If the back glass or screen is lifting or the phone rocks on a flat surface, the battery is swelling. Stop charging it, keep it away from heat, do not puncture it, and replace it promptly — a swollen lithium cell can rupture or ignite and crack the curved display from inside.