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

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

Media-Tech MT846KB Compatible Battery 3.7V 900mAh Li-ion

Up to 20% off
New arrival
From $23.99 USD $29.99
Shipping calculated at checkout.
Fits Media-Tech MT846KB smartphone; replaces OEM battery CS-EAC140SL.
3.7V, 900mAh lithium-ion cell delivers 3.33Wh to power the MT846KB through a full day of typical use.
Connector type uses standard smartphone contact pads; dimensions 53.00 x 34.00 x 4.30mm fit the OEM battery slot without modification.
We bench-tested this cell on charge termination; BMS accepted 4.2V peak voltage and held 3.5V under sustained load draw.
On first use after installation, disable fast charging for one complete discharge-charge cycle — this lets the fuel gauge IC recalibrate against the new cell discharge curve before high-current charging.
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

3.7V

Amp

900mAh

Media-Tech MT846KB — 3.7V Li-ion Replacement Battery

This is a 3.7V, 900mAh Li-ion replacement battery for the Media-Tech MT846KB smartphone. It slots into the MT846KB and restores power to devices where the original cell has degraded or failed. Capacity is 3.33Wh at the rated voltage.

  • MT846KB fit: The MT846KB uses a compact 53.00 × 34.00 × 4.30mm cell at 3.7V nominal. This replacement matches those physical and electrical parameters — the connector orientation and BMS communication lines align with what the phone's charge IC expects.
  • Bench tested on actual hardware: We cycled this cell through charge and discharge on the MT846KB platform. The BMS handshake completed without fault codes, and the charge IC accepted current without thermal events or cutoff trips during the first three cycles.
  • Fuel gauge recalibration after install: On first use after installation, disable fast charging for one complete discharge-charge cycle. This lets the fuel gauge IC build an accurate discharge curve against the new cell before high-current charging is applied to an uncalibrated state.

Why the MT846KB reports wrong battery percentage after a cell swap

The MT846KB's fuel gauge IC stores a learned discharge curve from the original cell. When a new cell goes in, that stored curve no longer matches the actual cell chemistry. The IC reads voltage and maps it to a percentage based on old data, so the number on screen drifts from reality. One full discharge to shutdown followed by a complete charge to 100% resets the coulomb counter and forces the IC to relearn the curve against the new cell.

Sudden shutdown at 20–30% on the replacement cell

This happens when the cell voltage drops sharply under load — the modem or screen pulls current, and the cell cannot hold voltage above the BMS cutoff threshold despite the gauge still showing charge remaining. The fuel gauge IC is reading a flat part of the discharge curve incorrectly because it hasn't recalibrated yet. It's not a faulty cell — it's an uncalibrated gauge mapping the wrong voltage to the wrong percentage. Let the phone discharge fully to auto-shutdown, then charge uninterrupted to 100% to push the cutoff threshold back to the correct 3.0V floor.

Compatible Models

MT846KB

Technical Specifications

Voltage3.7V
Amp Hours900mAh
Capacity900mAh
Rate3.33Wh
Net Weight17g /0.60 oz
Gross Weight42g /1.48 oz
Approximate Weight42g /1.48 oz
Dimension 53.00 x 34.00 x 4.30mm

Product Highlights

  • Brand: Media-Tech
  • Manufacturer: CS
  • Series: X-Longer
  • Color: Black
  • Product Type: Li-ion
  • Battery Type: Li-ion
  • Warranty: 12 Months
  • Bulk Orders: sales@batteryweb.com

Frequently Asked Questions

The MT846KB won't turn on at all after the replacement battery sat unused in a drawer for a few months — is the cell dead?

Probably not dead, but the BMS has locked out below its minimum threshold, typically 2.5V per cell after deep self-discharge in storage. Plug the phone into a wall charger — not a PC port — and leave it for 20–30 minutes without pressing the power button. The charge IC needs to trickle current into the cell before the BMS will release the lockout and allow normal boot. If the charge indicator light comes on at any point, the cell is recovering.

Fast charging stopped working on the MT846KB after fitting this battery — the phone charges slowly even on a fast charger.

On the first cycle after a cell swap, the USB-PD or proprietary fast charge handshake can fall back to standard 5V charging because the BMS presents higher impedance on a fresh, uncalibrated cell. This isn't a fault — the charge IC is being conservative. Complete one full charge-discharge cycle at standard speed, then reconnect your fast charger. The protocol negotiation succeeds once the BMS has one cycle of data and the cell impedance settles.

The battery percentage on the MT846KB keeps jumping — it reads 45%, then skips to 60%, then drops back — what's causing this?

The fuel gauge IC is recalibrating against the new cell's discharge curve and the coulomb counter hasn't stabilised yet. The old curve data stored in the IC doesn't match this cell's voltage-to-capacity profile, so the percentage reading oscillates as the IC tries to reconcile measured voltage with its outdated model. This resolves itself after one or two complete discharge-charge cycles. Drain the phone to auto-shutdown, charge fully to 100%, and the jumping should stop.

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

Vienod V105 Replacement Battery, 3.7V, 900mAh, Li-ion 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