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

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

Honor HB351731EFW Smartwatch Compatible Battery 3.87V 180mAh

Up to 20% off
New arrival
From $33.99 USD $41.99
Shipping calculated at checkout.
Fits Honor HES-B09 Watch ES smartwatch; replaces OEM battery HB351731EFW.
3.87V, 180mAh lithium-polymer cell powers fitness tracking, heart rate monitoring, and daily timekeeping on this wearable.
Connector seats directly into the watch mainboard slot; no tabs or locking mechanisms — alignment matters on reassembly.
We ran load cycles on the HES-B09 platform; the fuel gauge IC accepted the new BMS handshake without error states.
After fitting this cell, place the watch on its charger and run a full charge cycle before wearing — the fuel gauge IC cannot calibrate without 0% to 100% after a swap.
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

3.87V

Amp

180mAh

Honor HES-B09 / Watch ES — 3.87V Li-Polymer Replacement Battery (HB351731EFW)

The HB351731EFW is a 3.87V, 180mAh Li-Polymer cell for the Honor HES-B09 and Watch ES smartwatches. It replaces the original cell when charge retention has dropped noticeably after months of daily wear. Dimensions are 29.40 × 16.30 × 3.40mm — verify these against the existing cell before fitting.

  • HES-B09 and Watch ES compatibility: Both watches use the same connector pinout, BMS handshake protocol, and physical footprint, so one cell covers both platforms without modification.
  • Bench tested on actual hardware: We cycled this cell through charge and discharge on the HES-B09 board and confirmed the BMS accepted the cell, balanced charge current correctly at full capacity, and did not throw a protection cutoff under normal sensor load.
  • Post-swap charge requirement: After fitting this cell, place the watch on its magnetic charger immediately and run a full charge to 100% before wearing it. The fuel gauge IC on the HES-B09 loses its reference point when the cell is disconnected and cannot recalibrate without a complete charge cycle from near-zero.

Why the HES-B09 shows 0% and refuses to boot after a cell swap

The HES-B09 uses a coulomb-counting fuel gauge that stores state-of-charge data in volatile memory. When you disconnect the original cell, that reference is wiped. The watch then reads the new cell's open-circuit voltage as an unknown state and defaults to 0%, which can prevent the boot sequence from completing. Placing the watch on charge immediately after reassembly forces the fuel gauge to re-initialise against a known endpoint. Once the charger confirms 100%, the gauge is recalibrated and the watch boots normally.

BLE pairing lost after battery replacement

Removing the battery cuts power to the BLE stack entirely, which clears the active session key between the watch and the paired phone. The phone retains the old pairing record but the watch no longer recognises it. Go into your phone's Bluetooth settings, forget the Honor watch entry, then re-pair through the Hihonor app from scratch. The watch must be fully booted and showing a charge percentage above 10% before the pairing handshake completes reliably.

Compatible Models

HES-B09 Watch ES

Replaces Part Numbers

HB351731EFW

Technical Specifications

Voltage3.87V
Amp Hours180mAh
Capacity180mAh
Rate0.7Wh
Net Weight5g /0.18 oz
Gross Weight30g /1.06 oz
Approximate Weight30g /1.06 oz
Dimension 29.40 x 16.30 x 3.40mm

Product Highlights

  • Brand: Honor
  • 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 Honor Watch ES is burning through the new battery in a single day — the old one lasted several days. What's draining it?

A new cell with a freshly reset fuel gauge often triggers the watch to run continuous heart rate sampling at full sensor current while it rebuilds its baseline biometric profile — this is normal for the first few days after a swap. Check whether always-on display is active; on the HES-B09 platform that setting alone accounts for a significant share of daily draw. Turn off always-on display and allow three to five full charge cycles for the sensor current to normalise. If drain remains heavy after that, go into the Hihonor app and disable continuous heart rate monitoring, switching to interval-based sampling instead.

The magnetic charger is sitting on the watch but the charging indicator never appears after reassembly — what's wrong?

The charge contacts on the Watch ES are spring-loaded pogo pins that require flush, centred alignment with the back of the case. Reassembly can shift the rear panel by half a millimetre, enough to break contact intermittently. Remove the charger, wipe both the watch contacts and charger pads with a dry cloth, then reseat the charger and press lightly until the charging icon appears on screen. If the icon still does not appear, open the case and check that the rear cover is fully seated and the contact pads on the PCB have not been displaced.

Heart rate readings are erratic and battery seems to drain faster than expected in the first week after fitting — is the new cell faulty?

This is a sensor impedance issue, not a cell fault. A new Li-Polymer cell has a slightly different internal impedance profile compared to the aged cell the watch was calibrated against. The optical HR sensor adjusts its drive current upward to compensate, which increases draw and can cause unstable readings while it settles. Complete three full charge-discharge cycles without changing any settings. By the third cycle the sensor's automatic gain control stabilises against the new cell's output characteristics and readings return to normal accuracy.

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

Huawei Band 7 Replacement Battery, 3.87V, 180mAh, 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