The BN46 battery model name is a Xiaomi code, and spare part records pair it with the Redmi Note 8, the Redmi Note 8T and the Redmi 7. The pack is described as a 4000 mAh typical Li-ion polymer cell. The BN prefix points only to the maker group, which covers Redmi, Mi and POCO, so the exact phone names in the table are what count.
Many people write the code as "bn 46", leaving a gap in the middle. It points to the very same pack. The Redmi Note 7 and the Redmi 8 look and measure much like these phones, but neither one uses this code. So the look of a phone or the name of its series cannot tell you which battery to buy. You will find the marking on the label of the battery itself, and you can see it only after a technician takes off the back cover.
Quick facts
Step by step
Write down the phone name and model number
Open Settings, tap About phone and note the device name. If the model number is missing, type model in the Settings search bar.
Have the sticker on the old pack read out
The technician opens the back and reads
BN46from the sticker, together with capacity and voltage. Do not pull or peel the pack yourself.Lay the new pack beside the old one
Code, connector shape and outer size should agree, and the capacity should be close to the old figure.
Judge print and weight before fitting
Crisp print, batch details and a heft close to the old pack are good signs. A very light pack with a much bigger mAh claim is a bad sign.
Phones that use the BN46 battery model name
Spare part records name three phones for BN46. The Redmi Note 8 and the Redmi 7 are the ones Indian owners ask about most. The Redmi Note 8T is a sibling of the Note 8 and is paired with the same pack. Use the table as a guide, and let the sticker on your own battery settle any doubt.
| Phone | Status | Note |
|---|---|---|
| Redmi Note 8 | Matched by most listings | 4000 mAh typical |
| Redmi Note 8T | Matched by most listings | Mostly a global model, check your phone name first |
| Redmi 7 | Matched by most listings | Same capacity, different phone body |
| Redmi Note 8 Pro | Different battery | Larger pack, not a BN46 phone |
| Redmi Note 7 | Different code | See the BN4A page |
Every phone is covered on a separate page. See the Redmi Note 8 battery page and the Redmi 7 battery page.
Redmi Note 8 versus Redmi Note 8 Pro: one word, two packs
At the repair counter, the word Pro is where most wrong orders begin. The plain Redmi Note 8 takes BN46 at 4000 mAh typical. The Redmi Note 8 Pro carries a bigger pack with a different code, so a BN46 will not suit it, and its pack will not suit the plain Note 8.
Check the complete phone name on the box, or open the About phone screen to see it. When the name reads just Redmi Note 8, BN46 is the one to expect. When the word Pro shows up anywhere in it, stop and confirm the correct code before you pay.
An owner brought a Note 8 that ran flat by afternoon. The shop had a bigger-looking pack that was made for a Pro. The technician read BN46 off the old sticker, rejected the Pro pack because its connector and size were off, and ordered the exact code.
Rated and typical capacity of BN46
The 4000 mAh number is the headline value used on phone pages and parts lists. Xiaomi packs usually print a rated (minimum) value a little under it, so read that from your own battery instead of guessing.
Stored energy can be found from the mAh figure. Take the capacity, then multiply by the voltage, and finally cut that number down by dividing with 1000. At a listed 3.85 V, a 4000 mAh pack gives about 15.4 Wh. If two packs share the same mAh but one has a different voltage, their energy will not match, so check both numbers printed on the label.
Hours of use in daily life depend on brightness, network signal, apps and the age of the cell. A fresh BN46 on a Redmi Note 8 can carry a day of mixed use, though your result will differ.
Codes that get confused with BN46
Redmi codes carry numbers that run close together, and the print on old stickers fades. These cause the most slips:
- BN4A is a separate code with its own phones, so do not treat it as a twin of BN46.
- BN45 and BN44 sit right beside BN46 in number but have their own pages and phones.
- The Redmi 8 looks much like the Redmi 7 from the front, yet it takes a bigger pack with another code. Check the Redmi 8 page.
Neighbouring numbers never mean interchangeable packs. To see every Xiaomi code together, open the Redmi battery model list.
Signs a BN46 pack is wearing out
These phones are several years old, so many original packs are tired. Match what you see to the table.
| Symptom | Probable reason | Action |
|---|---|---|
| Charge falls steeply soon after unplugging | Cell capacity has faded with age | Run a health check and plan a swap |
| Sudden power off with charge showing | Aged cell cannot support heavy use | Ask a technician for a load test |
| Back cover gaps or lifted screen | Swollen cell | Power down and visit a service centre the same day |
| Note 8 warm with the screen off | Busy background app or a bad pack | Reboot, remove the cover, then get it examined |
Quick drain can also come from apps and weak signal, so read why the charge disappears quickly before blaming the cell, and then follow the battery health check steps.
Watch for a swollen back panel, a screen that is rising, or a pack that leaks or has a strange smell. In that case, power the phone down and leave it off the charger in a cool place. Never press or bend the pack. Fake packs that promise much more than 4000 mAh are widespread, so buy only one that clearly shows BN46 on its own body.
Getting a new BN46 pack fitted
The Redmi Note 8 and the Redmi 7 both have glued backs and non-removable batteries, so leave the opening to the maker's service point or a reliable local technician. Carry the phone, its model number and a picture of the old label if you have one.
When the new pack arrives, check these points:
- The code reads BN46 and the print is clean.
- The weight is close to the old pack.
- The capacity is near 4000 mAh, not 5000 or 6000.
- The connector is the same as the old one.
More fitting advice is in the mobile battery replacement guide.
Keep the old pack for a few days after the swap. If the new one acts oddly during its first full charge, you still have the original label to compare.
Looking after an older Redmi Note 8 or Redmi 7
Phones of this age run warm during games and video calls, and heat wears a cell faster than anything else. Remove a thick case while charging, and do not leave the phone on a sunny window sill or in a parked vehicle.
Pick a charger and cable that are in good shape, and throw away any cable that heats up close to the plug. Avoid keeping the phone at a full charge for many hours every day. Once a fresh pack is fitted, just use the phone as usual. It needs no special first-charge routine.
Frequently asked questions
Which phone uses the BN46 battery?
Most records pair BN46 with the Redmi Note 8, the Redmi Note 8T and the Redmi 7, as a 4000 mAh typical pack. The sticker on your current battery is the final proof.
Is BN46 the Redmi Note 8 battery model name?
Yes, for the standard Redmi Note 8. The Redmi Note 8 Pro is another phone with another pack, so BN46 is the wrong part for that model.
How many mAh is the BN46 battery?
The seller lists this pack as 4000 mAh typical. The rated (minimum) figure printed on its label can be a little lower. Check the label on your own battery to be certain.
Can I use a BN46 battery in the Redmi Note 7?
No. The Redmi Note 7 has its own code, and a pack of similar size may not suit the connector. Match the exact code instead.
Is bn 46 written with a space the same as BN46?
Yes. The space is only how people type it. The sticker shows the code written together as BN46.
How can I tell if a BN46 battery is fake?
Fakes tend to weigh less than the old pack, carry blurry print with no batch marks, and boast far above 4000 mAh. Compare code, weight and connector with the pack you removed.