Free DIY Guide

Phone Battery Replacement

Diagnosing real battery failure, buying the right replacement battery, opening the phone without breaking it, and calibrating correctly after. All of it.

This is an in-person only repair -- you can't swap a battery over a video call. A Geek comes to you for $89.99, done in 30 minutes.

I'll do it myself ↓

45 min -- 2 hrs depending on phone model

Intermediate to Advanced difficulty

Full backup required before starting

Your phone is dying. You have two choices: replace the battery or replace the phone. One costs $89.

Before you start:

•Drain your battery below 25% before opening the phone. A fully charged lithium battery is a fire risk if punctured during prying.
•Back up your phone completely before opening it. Data loss during repair is possible if a connector is damaged.
•Never use metal tools to pry up a swollen battery -- it can puncture the cell and cause thermal runaway. Use heat and plastic tools only.
•iPhones 13 and later use parts pairing -- a genuine Apple battery is required to restore the Battery Health percentage display. Third-party batteries work but show a service message instead of a percentage.
•IP water resistance is compromised after any repair. The phone will not be IP68 rated after a DIY battery replacement regardless of how carefully you reseal it.
•Do not reconnect the display before connecting the battery -- some phone models can damage the logic board if the display is connected before the battery provides a ground reference.

What you'll need

Specific tools vary by phone model -- look up your exact model on iFixit.com first. Affiliate links go to Amazon search results. Prices vary -- we don't set them.

iSclack or suction cup opening toolFind on Amazon

For iPhones and most modern Android phones, the back glass or screen is adhered with strong adhesive. A suction cup gets enough lift to work a pick underneath without cracking the panel.

Pentalobe screwdriver (for iPhones) or Torx T2/T3 (for Android)Find on Amazon

iPhone bottom screws are pentalobe -- a standard Phillips will strip them immediately. iFixit's pentalobe P2 handles iPhone 7 through 15. Check your Android model for the specific Torx or Phillips size.

Phillips #000 screwdriverFind on Amazon

For the tiny internal screws on battery brackets and connector shields inside virtually every phone. Do not use a worn-out bit -- stripped screws inside a phone are a disaster.

Plastic opening picks (set of 5+)Find on Amazon

For prying up adhesive. Metal picks and spudgers can damage flex cables or leave marks on components. Use plastic, especially near the screen.

Spudger (plastic)Find on Amazon

For disconnecting battery and cable connectors inside the phone. Connector ZIF connectors flip up; some connectors pull straight out. A plastic spudger applies the right force without shorting anything.

Heat gun or iOpener heating padFind on Amazon

Modern phones use stretch-release adhesive strips under the battery, but they still need gentle heat (around 80°C) to soften the adhesive at the perimeter before opening. A heat gun on low, or the iOpener microwave pad, works. A hair dryer on high works too -- just move it constantly.

Replacement battery (from a reputable source)Find on Amazon

For iPhones: iFixit and OEM Apple Service Program batteries are the best options. Avoid no-name Amazon batteries -- capacity is often 20--30% less than advertised and they may not charge correctly. For Android: iFixit, official Samsung/Google service batteries, or Batteries Plus for in-store options.

Adhesive strips (usually included with battery)Find on Amazon

Pre-cut adhesive strips to re-secure the battery. Most third-party battery kits include these. If yours doesn't, buy iFixit's adhesive strips for your specific model.

Anti-static wrist strap or grounding matFind on Amazon

Your body carries static that can damage logic board components. Ground yourself by touching bare metal before working on phone internals. A wrist strap connected to a grounded outlet is more reliable.

Magnetic project matFind on Amazon

Tiny screws are magnetic and the mat holds them in position with labels. Without one, you will lose screws. This is not a maybe -- you will lose them.

The steps

All 8 steps. Do not skip Step 3 -- the backup.

Diagnose your battery -- confirm replacement is actually needed

Bad battery symptoms: phone dies at 20--30% charge instead of 0%, phone randomly shuts off under load, battery drains from 100% to 0% in under 6 hours with normal use, phone is warm all the time even when idle, performance throttling (apps feel slow even though they weren't before), or battery swelling (a visible bulge under the back glass -- replace this one immediately). For iPhones (iOS 11.3+): Settings → Battery → Battery Health & Charging. Under 80% maximum capacity is Apple's threshold for replacement. Performance Management (throttling) will be enabled automatically. If it says "Your battery's health is significantly degraded," that's the system telling you it's time. For Android: no universal built-in check. The AccuBattery app (free on Google Play) measures battery health over a few charge cycles by comparing your battery's actual capacity to its rated capacity. AccuBattery gives a percentage health reading similar to iOS Battery Health. Samsung devices have a hidden battery diagnostic: dial *#0228# to open the Battery Status screen. Also check: Settings → Battery → Battery Usage. Look for any single app consuming more than 20% in the background. Sometimes what feels like a bad battery is actually a runaway app -- kill it and see if drain improves before replacing the battery. A battery at 79% health isn't always worth replacing if your usage is light. A battery at 79% health with a phone that throttles during video calls or dies at 25% charge is absolutely worth replacing.

Pro tip: If your iPhone is charging slowly or not charging at all, check the Lightning/USB-C port for lint before assuming battery failure. A compressed air blast or a toothpick clearing the port has 'fixed' many phones that appeared to have battery problems.

OEM vs. aftermarket battery -- the only recommendation that matters

Use an OEM or high-quality third-party battery. Do not use the cheapest Amazon listing. Here is exactly why: Cheap batteries (under $10--15 on Amazon): capacity is often 20--30% below the listed mAh. An iPhone 13 should have a 3,227 mAh battery. Cheap replacements frequently measure 2,400--2,600 mAh in testing. You'll replace the battery, notice it's only marginally better, and not understand why. Additionally, cheap batteries use lower-quality cells that degrade faster and in some cases have inadequate BMS (Battery Management System) protection -- overcharge and over-discharge protection is weaker or absent. iFixit batteries: the gold standard for third-party. They partner with third-party manufacturers that meet or exceed OEM spec. iFixit also includes all necessary tools and adhesive. Costs $30--50 depending on model. Worth it. iFixit Fix Kits vs. parts-only: the Fix Kits include the battery, tools, and adhesive. If you don't already own the right tools, the kit is a better deal than buying parts separately. Apple's Independent Repair Provider program: Apple provides genuine parts to authorized independent shops. This is the highest-quality option short of going to Apple directly. A genuine Apple battery in your independent shop is the same as an Apple Store battery. Android: Samsung and Google both sell service parts through iFixit and through authorized service centers. Avoid OEM batteries sold by unknown third parties on Amazon -- even if they claim "genuine" -- unless they're fulfilled by iFixit or a known source.

Pro tip: Look up your specific phone model on ifixit.com/Guide before buying anything. iFixit rates repair difficulty (1--10) and lists exactly what parts and tools are needed. The iPhone 16 Pro has a different opening procedure than the iPhone 14 -- don't assume the process is the same across models.

Back up your phone completely before opening it

There is a non-zero chance this goes wrong. Dropped connector, cracked display adhesive, stripped screw, bent flex cable -- any of these can render the phone inoperable. Back up everything before opening the case. iPhone: Settings → [your name] → iCloud → iCloud Backup → Back Up Now. Wait for it to complete. Confirm the backup timestamp updates. Alternatively, connect to a Mac/PC and back up through Finder/iTunes. Android: Settings → Accounts → Backup → Back up to Google Drive. For Samsung: Samsung Cloud is separate from Google backup -- back up to both. Photos: confirm Google Photos has backed up all recent photos (tap the cloud upload icon in Google Photos and wait for "Backup complete"). Also: note any apps that don't support cloud backup and whose data you care about (some games, authenticator apps, etc.). 2FA apps (Google Authenticator, Authy) should be set up with multi-device backup -- if you lose your phone, you need access to your 2FA codes. Drain the battery to under 25% charge before the repair: lithium batteries store energy and a damaged or punctured battery can catch fire. Less charge = less risk if something goes wrong during the pry-open step.

Pro tip: Write down your phone's IMEI before the repair (Settings → General → About on iPhone). If anything goes wrong and you need a warranty claim or police report, you'll need it.

Opening the phone -- this is where most DIY repairs go wrong

Opening procedure varies significantly by model. Look up your specific model on iFixit before starting. Here's the general process for modern adhesive-back phones (most iPhones and many Android phones): Heat the edges: apply heat to the edges of the phone -- particularly the bottom edge -- using a heat gun on low (about 80°C), an iOpener pad, or a hair dryer on high held 2--3 inches away for 90 seconds, moving constantly. You're softening the perimeter adhesive. Do not overheat -- 80--90°C is the target. At 100°C+ you risk delaminating the display. Suction cup and picks: apply the suction cup to the screen (for bottom-opening phones) or back glass (for back-opening phones). Pull gently while inserting a plastic pick into the gap. Slide the pick around the perimeter to break the adhesive seal. Do not pry deeply -- you're separating adhesive, not levering the entire panel. Open slowly: as the adhesive releases, open the panel like a clamshell, rotating along the top edge or side hinge point specified in your iFixit guide. There are flex cables connecting the panel to the logic board -- do not pull the panel more than 90 degrees before locating and disconnecting them. Cable disconnect: before lifting the panel fully, identify and disconnect the display/digitizer cable connectors. They typically sit under a metal shield bracket held by tiny Phillips screws. Remove the bracket screws, lift the bracket, then pop the connectors up with a plastic spudger. Now the panel can be set aside.

Pro tip: Record a video of each disassembly step with your phone propped on a book. You'll want to watch it during reassembly. This sounds excessive. It saves the repair every time.

Remove the old battery

Modern phones use pull-tab adhesive strips (stretch-release adhesive) to hold the battery down. These are the thin plastic tabs that pull out at a low angle to release the battery without prying. Locate the adhesive pull tabs: they typically extend from under the battery toward the bottom of the phone. On many iPhones, there are two tabs -- pull them slowly, maintaining a low angle (nearly parallel to the phone surface). If they break off, you'll need to heat the phone back up and pry the battery out, which is riskier. Pull technique: grip the tab with tweezers or fingernails, pull slowly and continuously at a ~30-degree angle to the battery surface. "Slowly" means taking 20--30 seconds to pull it out. Fast pulls snap the tabs. If the tab breaks: apply more heat to the bottom of the phone, insert a plastic pick under the battery edge, and gently lever it up with very light prying force. Do not use a metal pick for this. Puncturing the battery causes thermal runaway -- smoke, fire, and a bad day. If the battery starts to deform, stop. Once the battery is free: disconnect the battery connector from the logic board (the ZIF or press-fit connector on the cable coming from the battery). Use a plastic spudger to lever it straight up -- don't pry sideways. Dispose of the old battery: lithium batteries cannot go in regular trash or recycling bins. Best Buy, Home Depot, and Staples all have free battery drop-off. iFixit ships batteries in containers suitable for returning old batteries via their recycling program.

Pro tip: The battery connector on some phones is covered by an adhesive-backed bracket. Check your iFixit guide for the exact connector style before you pry -- some flip up, some pull straight out, and treating one like the other breaks the connector.

Install the new battery

Clean the battery area: remove any remaining adhesive with isopropyl alcohol (90%+ concentration) on a cotton swab. The new adhesive strips won't bond properly if there's old adhesive residue. Install new adhesive strips (if they're separate from the battery): peel off the backing on one side and apply them to the bottom of the battery bay following the included diagram. Press firmly to bond. Connect the battery: plug the battery connector into the logic board first, before placing the battery. Press firmly until it clicks or seats flush. This is the order for most phone models -- connector in, then battery down. Doing it in the wrong order strains the cable. Lower the battery into position: align it carefully (most batteries have only one orientation that fits). Press down firmly on the adhesive to bond it to the back case. Apply pressure for 30 seconds. Do not reassemble immediately: press the power button to confirm the phone powers on before fully reassembling. If it doesn't power on -- check the battery connector, check the display connector, and confirm there's charge in the new battery (some batteries ship at 20--30% charge). If still no power -- stop and diagnose before closing the phone.

Pro tip: Plug the phone into a charger before pressing power. Some new batteries ship with very low charge and won't start the phone on their own, but will power on when connected to power.

Reassemble and seal

Reconnect the display cable: press the connectors back into their sockets, replace the metal bracket, and reinstall the tiny bracket screws. Confirm each screw is in the right hole -- mixing up screw lengths inside a phone strips the threads in the logic board (very bad). Close the panel: align the panel to the case. Press the edges down firmly, working around the perimeter. You'll feel and hear the adhesive and clips engaging. On most phones, you need to press firmly along the bottom edge, then side edges, then the top edge -- follow the iFixit guide for your specific model. Reinstall the bottom screws: the pentalobe or Torx screws go back in at the bottom. Do not overtighten -- finger-tight plus about a quarter turn. These screws are short and thread into aluminum -- they strip easily. Press and hold: lay the phone on a flat surface and press down across the entire back for about 30 seconds to bond the new adhesive. Some repair guides recommend placing the phone under a book for 5--10 minutes. Either works. IP water resistance: if your phone had IP67 or IP68 water resistance, you have compromised it by opening the phone. Replacement adhesive restores most of the seal, but it will not be as good as factory. Avoid submerging the phone for at least 24 hours after repair, and avoid water exposure beyond incidental splashing going forward.

Pro tip: Before pressing the back panel fully down, double-check that no cables are routed over the seam between the panel and the case. A cable pinched under the panel will break when you press the panel closed.

Calibrate the battery after replacement

Battery calibration is important after any replacement to get accurate charge readings. iOS calibration: the iPhone's battery health gauge re-calibrates automatically after 2--3 full charge cycles. You'll see "Calibrating..." under Battery Health for the first day. Your health reading may show unusually high or low until calibration is complete -- this is expected. Android calibration: similar process. Charge to 100%, let it sit connected for another 30 minutes, then use normally until it drains to under 10%. Do this 2--3 times. AccuBattery will show your actual measured capacity approaching the battery's rated capacity as calibration cycles complete. What to watch for in the first 48 hours: does the percentage drop faster than expected early in the charge cycle? That's normal -- the gauge needs calibration. Does the phone shut off at 15% or above? That indicates a bad battery or a deep calibration issue -- try a full drain/charge cycle first. iPhone Battery Health after replacement: immediately after replacement, Battery Health may show 95--100% or may show a message about "service recommended." A third-party battery will show "Important Battery Message" in Battery Health on iPhone 13 and later due to Apple's parts pairing security feature. The phone will work fine -- you just won't see the health percentage for a third-party battery. This is Apple's policy, not a defect. If you want iOS Battery Health to show the percentage and not the service message, you need either a genuine Apple battery installed by an Apple Authorized Service Provider, or a battery from Apple's Independent Repair Provider program.

Pro tip: Set a reminder to check battery health 30 days after replacement. A quality replacement should read above 95%. If it reads below 90% after 30 days of light use, you got a substandard battery -- return or replace it while you can.

Rather not open the phone yourself?

A Geek comes to you with the right battery for your model, the right tools, and does the swap in about 30 minutes.

From $89.99 on-site

Same-day available · Satisfaction guaranteed

In-person only service

Battery replacement is a hands-on repair -- we can't do it over a video call. Book an on-site visit above and a Geek comes to you.

By the numbers

DIY time45--120 min

Geek time~30 min

iOS replacement thresholdunder 80% health

Adhesive tabs that breakmore than you'd think

Charging all the way to 100% again?

If your phone lasts a full day again and the battery percentage moves like it used to -- that's the whole point. Well done.

If the adhesive tab snapped, the pull didn't work, or the phone won't turn on -- stop where you are and let us take it from here before something worse happens.