Redmi Note 7 BN4A Compatible Battery 3.85V 3900mAh
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.
Redmi Note 7 BN4A Compatible Battery 3.85V 3900mAh - is backordered and will ship as soon as it is back in stock.
Let customers speak for us
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
✉ sales@batteryweb.com
Battery Care Tips
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
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
⚠️ 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.
Redmi Note 7 BN4A Compatible Battery 3.85V 3900mAh - is backordered and will ship as soon as it is back in stock.
Voltage
3.85V
Amp
3900mAh
Redmi Note 7 — 3.85V Li-Polymer Replacement Battery (BN4A)
The BN4A is a 3900mAh (15.02Wh) lithium-polymer cell that replaces the original battery in the Redmi Note 7. It fits models M1901F7G, M1901F7H, M1901F7C, and three additional regional variants. When the original cell degrades — losing hold-charge or triggering unexpected shutdowns — this cell restores the power rail the phone depends on.
- Note 7 variant compatibility: The M1901F7G, F7H, and F7C share the same chassis dimensions, connector pinout, and BMS handshake protocol. One cell fits all three without connector modification.
- Bench tested on actual hardware: We ran the BN4A through full charge and discharge cycles on the Note 7 board. The BMS negotiated charge termination correctly, and the protection circuit tripped as expected on an induced over-discharge condition.
- Fuel gauge recalibration on first use: On first use after installation, disable fast charging for one complete discharge-charge cycle. This lets the fuel gauge IC map the new cell's discharge curve before high-current fast charging pushes current into an uncalibrated state.
Sudden shutdown at 20–30% on the replacement cell
The Note 7's PMIC uses a coulomb counter calibrated to the original cell's voltage curve. A fresh cell has a steeper voltage drop in the lower charge window, so the PMIC hits its cutoff threshold earlier than the displayed percentage suggests. The fix is one full uninterrupted discharge down to automatic shutdown, followed by a full charge — no interruptions. After that cycle, the fuel gauge IC recalculates its internal model against the actual cell behaviour.
Phone not powering on after BN4A sat in storage
Li-polymer cells shipped at storage charge (around 40–50%) can drop below the BMS lockout threshold — typically 2.5V per cell — if left unused for several months. When that happens, the BMS cuts output entirely and the phone shows no response on the charge indicator. Connect to a 5V charger and leave it untouched for 20–30 minutes before attempting to power on — the charge IC needs to trickle current past the BMS re-enable threshold before normal charging resumes.
Compatible Models
Replaces Part Numbers
Technical Specifications
Product Highlights
- Brand: Redmi
- Manufacturer: CS
- Series: X-Longer
- Color: Black
- Product Type: Li-Polymer
- Battery Type: Li-Polymer
- Warranty: 12 Months
- Bulk Orders: sales@batteryweb.com
Frequently Asked Questions
My Redmi Note 7 keeps shutting off at around 25% after I put in the new BN4A — what's causing it?
The fuel gauge IC is still using the discharge curve it mapped to the old, degraded cell. The new cell has a different voltage profile in the lower range, so the phone's PMIC trips its cutoff before the cell is actually empty. Run one full discharge to automatic shutdown followed by a complete uninterrupted charge — this forces the coulomb counter to recalibrate against the actual BN4A curve. After that single cycle, the early shutdowns typically stop.
Fast charging stopped working the first time I plugged in after fitting the BN4A — is the charger faulty?
The charger is almost certainly fine. On the first charge cycle, the Note 7's charge IC runs a handshake to verify the BMS on the new cell before allowing high-current input — if that handshake doesn't complete cleanly, it falls back to standard 5V charging. Disconnect the cable, power the phone off completely, then reconnect to the fast charger from a cold start. Most first-cycle fast charge failures clear on the second connection once the BMS has completed its initial charge termination sequence.
The battery percentage on my Note 7 is jumping around erratically — sometimes gaining or dropping 10% in seconds. Is the BN4A faulty?
Erratic percentage jumps after a cell swap are almost always a fuel gauge IC issue, not a faulty cell. The coulomb counter is recalibrating against measurement data it hasn't collected yet from the new cell. Let the phone run through two full discharge-charge cycles without interruption — avoid topping up mid-cycle during this period. After the second full cycle, the fuel gauge IC has enough data to stabilise its readings.
Payment & Security
Payment methods
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
Related Products
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.
-
Up to 21% offNew arrival
BatteryWeb
CAT S60 Replacement Battery 3.85V 3500mAh APP-12F-F5757I-CGX-111
0.17 lb
Sale priceFrom $26.99 USD Regular price $33.99Unit priceIn stock (66 units) -
-
Up to 21% offNew arrival
BatteryWeb
Caterpillar S60 Replacement Battery 3.85V 3500mAh Li-Polymer
0.17 lb
Sale priceFrom $26.99 USD Regular price $33.99Unit priceIn stock (66 units) -
-
Up to 20% offNew arrival
BatteryWeb
Xiaomi Mi 9 BM3L Replacement Battery 3.85V 3200mAh
0.21 lb
Sale priceFrom $25.99 USD Regular price $31.99Unit priceIn stock (72 units) -
-
Up to 21% offNew arrival
BatteryWeb
Prestigio PSP7505DUO Replacement Battery 3.8V 1500mAh
0.12 lb
Sale priceFrom $26.99 USD Regular price $33.99Unit priceIn stock (60 units) -
-
Up to 20% offNew arrival
BatteryWeb
Xiaomi Redmi Note 7 BN4A Replacement Battery 3.85V 3900mAh
0.23 lb
Sale priceFrom $25.99 USD Regular price $31.99Unit priceIn stock (69 units) -
-
Up to 21% offNew arrival
BatteryWeb
Honor Note 10 Replacement Battery 3.85V 4900mAh Li-Polymer
0.23 lb
Sale priceFrom $26.99 USD Regular price $33.99Unit priceIn stock (90 units) -
-
Up to 21% offNew arrival
BatteryWeb
Huawei Mate 20 X Compatible Battery HB3973A5ECW 3.85V 4900mAh
0.23 lb
Sale priceFrom $26.99 USD Regular price $33.99Unit priceIn stock (90 units) -
-
Up to 20% offNew arrival
BatteryWeb
Sony Xperia XA1 Ultra LIP1641ERPC Replacement Battery 3.8V 2700mAh
0.18 lb
Sale priceFrom $25.99 USD Regular price $31.99Unit priceIn stock (66 units) -
