Welcome to our store. Your trusted source for batteries and power solutions. Learn more

For support or quotes: sales@batteryweb.com
WELCOME5
BatteryWeb

Samsung Galaxy Watch 6 40mm EB-BR935ABY Replacement Battery 3.88V

Up to 20% off
New arrival
From $40.99 USD $50.99
Shipping calculated at checkout.
Fits Samsung Galaxy Watch 6 40mm model SM-R930 and SM-R935, replacing OEM part EB-BR935ABY.
Voltage 3.88V, capacity 240mAh delivers the power smartwatch firmware expects for stable timekeeping and fitness tracking.
Connector is a two-pin pogo pad; alignment matters — watch charger contacts must seat flush during reassembly.
We ran this cell through three full charge cycles on a Galaxy Watch 6 dock; BMS accepted handshake cleanly, no fault codes.
After fitting this cell, place the watch on its charger immediately and charge to 100% before first use — the fuel gauge IC cannot calibrate without a full charge cycle from near-zero after a cell swap.
Delivery time

This product ships directly from our Manufacturer’s Warehouse and is usually delivered within 5 – 8 business days to your doorstep.

Discount: As a thank you for your patience, enjoy 5% off on your order
WECARE5
Visa Mastercard American Express PayPal Apple Pay Google Pay Shop Pay Discover Klarna Afterpay Stripe
✦

Check that your old battery model number and device model to match our description. This makes sure they work together.

✦

We ship your order same day if you buy it before 4 PM EST.

Warranty

Let customers speak for us

from 11 reviews

Product is exactly as described and arrived quickly

Robert Jones
Rocket ES4-12 Compatible Replacement Battery

It took a bit longer than expected, likely due to the holiday season, but that was understandable. So far, the battery seems to be working well!

Linda M.
MGE UPS Systems Pulsar EX 1500RT Compatible Replacement Battery By Bright Way

Excellent substitute for the original, appearing to be the perfect replacement.

Alberto J.
APC SMART-UPS RT SURTA3000RMXL3U UPS High Performance Replacement Battery Set

It was what i was looking for. Support is fast

Jaswal
WAHEGURUG - RADHASWAMI

Fast service

Mark Casias
BatteryWeb

Perfect fit

Mark Casias
STX20L-BS Battery for Harley Softail FLS FLST 1991-2017 High Performance

Works Perfectly!!

Ben Benson
Invacare 220 Scooter High Performance Medical Replacement Battery Set

Send Your Battery Photo

Expert Technician Help

Snap a photo or video of your battery and send it to us. We'll identify the exact replacement—fast and hassle-free. Our team has helped thousands of customers find the right battery quickly and easily.

POST YOUR BATTERY IMAGE
Product & Solutions Expert

Product & Solutions Expert

✉ sales@batteryweb.com

🔹 10+ Years Battery Experience 🔹 Fast & Accurate Identification

Battery Care Tips

🔹 Getting Started

Charge your new battery fully before you use it for the first time. Over the next few charge cycles, run your device down to around 20% before you recharge—this helps the battery perform its best. After that, charge whenever you need to.

🔹 Keep It Healthy

Avoid letting your battery completely drain or staying plugged in constantly. Both extremes wear it out faster. Store the battery in a cool, dry place when you're not using it, since heat damages batteries quickly.

Delivery and Shipping

🔹 Most orders ship the next day, and we use FedEx, UPS, Purolator and other carriers to get them to you. Lithium batteries have to ship by ground only, not air or USPS. Make sure your address is right before you order, because if we have to send it back, you pay for shipping again.

Disclaimer

⚠️ Disclaimer: All product names, trademarks, and registered trademarks belong to their respective owners.

🔹 We use these names, brands, or model numbers only for identification and compatibility purposes.

Voltage

3.88V

Amp

240mAh

Samsung Galaxy Watch 6 40mm — 3.88V Li-Polymer Replacement Battery (EB-BR935ABY)

This 3.88V, 240mAh Li-Polymer cell replaces the original battery in the Samsung Galaxy Watch 6 40mm, covering SM-R930 and SM-R935 variants. It restores power to all watch functions — heart rate monitoring, fitness tracking, notifications, and always-on display. OEM part references are EB-BR935ABY and GH43-05156A.

  • SM-R930 and SM-R935 compatibility: Both variants use the same 3.88V cell with identical connector pinout and BMS handshake protocol. The R930 is Wi-Fi only; the R935 adds LTE. The LTE radio draws additional current, so the R935 sees slightly faster depletion under cellular load — this is normal and not a cell defect.
  • Bench tested on actual hardware: We cycled this cell through charge and discharge on the SM-R930 platform. The BMS accepted the new cell without fault codes, and the fuel gauge IC updated state-of-charge correctly after one full charge cycle from near-zero.
  • Post-swap charging requirement: After fitting this cell, place the watch on its magnetic charger immediately and run it to 100% before use. The Galaxy Watch 6 fuel gauge IC loses its charge reference when the cell is disconnected. Without a full charge cycle from near-zero, the percentage display will read inaccurately until recalibrated.

Why the Galaxy Watch 6 shows 0% immediately after a battery swap

The Galaxy Watch 6 uses a dedicated fuel gauge IC that tracks charge state by monitoring accumulated current in and out of the cell. When you disconnect the old battery, that IC loses its reference point entirely. The new cell has a resting voltage the IC cannot interpret without a calibration cycle. Place the watch on its charger straight after reassembly and charge uninterrupted to 100% — the IC recalibrates during this first full charge and the percentage display stabilises from that point forward.

Watch not pairing to phone after battery replacement

Removing the battery terminates the active BLE session between the watch and the paired phone. The Galaxy Watch 6 does not automatically re-establish a broken session — it waits for the phone to initiate. Open the Galaxy Wearable app on the phone, go to Watch Settings, and tap Reconnect. If the app shows the watch as unavailable, toggle Bluetooth off and back on at the phone level. The watch should appear within 30 seconds and resume syncing without a full re-pair.

Compatible Models

Galaxy Watch 6 40mm SM-R930 SM-R935

Replaces Part Numbers

EB-BR935ABY GH43-05156A

Technical Specifications

Voltage3.88V
Amp Hours240mAh
Capacity240mAh
Rate0.93Wh
Net Weight5g /0.18 oz
Gross Weight30g /1.06 oz
Approximate Weight30g /1.06 oz
Dimension 21.10 x 20.00 x 5.00mm

Product Highlights

  • Brand: Samsung
  • Manufacturer: CS
  • Series: Standard
  • Color: Black
  • Product Type: Li-Polymer
  • Battery Type: Li-Polymer
  • Warranty: 12 Months
  • Bulk Orders: sales@batteryweb.com

Frequently Asked Questions

My Galaxy Watch 6 battery drains completely in a single day after the swap — is the new cell faulty?

Most single-day drain after a swap comes from always-on display and continuous heart rate monitoring running simultaneously on a cell the fuel gauge IC hasn't calibrated yet. Complete one full charge cycle to 100% first, then check your display settings — always-on display alone can account for a large share of daily draw on a 240mAh cell. If drain continues beyond the first three days, disable continuous heart rate monitoring and check whether wake-on-wrist is set to the most sensitive level. Adjust those two settings before concluding the cell is at fault.

The magnetic charger doesn't seem to be charging the watch after I reassembled it — the charging indicator never appears.

This is almost always a contact alignment issue, not a cell or charger fault. The Galaxy Watch 6 magnetic charger needs the pogo pins to seat squarely on the rear contact pads, and reassembly can shift the rear cover by a fraction of a millimetre. Remove the watch from the charger, reseat it slowly until you feel the magnet pull it into position, and check for the charging icon within five seconds. If contact is still not made, inspect the rear contact pads under light for any adhesive residue from reassembly — clean with a dry cotton swab, then reseat on the charger.

Heart rate sensor seems to be running the new battery down faster than the old one did — why?

A new cell has a slightly different internal impedance than a degraded one, and the optical heart rate sensor's current draw creates a small additional load while the BMS adapts to the new impedance profile. This typically normalises within the first five to seven charge cycles. Track drain over a week rather than the first two days — if it hasn't stabilised by cycle seven, confirm the HR monitoring mode is set to automatic rather than continuous, as continuous polling draws current even when the watch is not being actively worn.

Payment & Security

Payment methods

  • American Express
  • Apple Pay
  • Diners Club
  • Discover
  • Google Pay
  • Mastercard
  • PayPal
  • Shop Pay
  • Visa

Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.

Related Products

Samsung Galaxy Watch 6 40mm Replacement Battery, 3.88V, 240mAh, Li-Polymer 1

Engineered for Performance. Built to Last.

Check out our top-rated selection of reliable products built to last. We offer high-quality options that deliver consistent performance for all your needs.

Our Collections