The BN54 battery model name points to a Xiaomi pack, and most spare listings match it to three phones: the Redmi Note 9, the Redmi 9 Prime and the POCO M2. Its advertised capacity is 5020 mAh typical. Some listings also name the Redmi 10X 4G, a phone that was not sold in India under that name.
People search this code in many shapes, such as "note 9 battery model", "mi note 9 battery model number" or "poco m2 battery model". The words Note 9 cause the most trouble, because the plain Note 9 and the Note 9 Pro are separate phones. Before paying for anything, look at the sticker on the pack in your hand, since a list on a screen cannot see your phone.
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 not shown, type model in the Settings search bar.
Check the box or invoice for the full name
Look for the words Redmi Note 9, Redmi 9 Prime or POCO M2. A name with Pro, Power or 5G at the end points to another battery.
Have the old pack read by a technician
The code
BN54is printed on the sticker beside the capacity. On a sealed phone the back must be opened first, so do not pull the pack out yourself.Lay the old and new packs side by side
Compare the code, the size, the connector and the weight. A pack that is clearly lighter than the old one deserves a second look.
Keep a photo of the old label
Take a clear photo before the old pack goes away. It saves a second trip if the first pack turns out wrong.
Phones that use the BN54 battery model name
Codes starting with BN appear on many Xiaomi, Redmi and POCO packs, yet those two letters only name the maker group. For BN54, most listings agree on three phones sold in India. The table shows each one and how firm the match is.
| Redmi handset | Status | Note |
|---|---|---|
| Redmi Note 9 | Matched by listings | 5020 mAh typical |
| Redmi 9 Prime | Matched by listings | Verify against the label printed on your removed pack |
| POCO M2 | Matched by most listings | Built much like the Redmi 9 Prime; its advert figure may read 5000 mAh, so check the label |
| Redmi 10X 4G | Named in some listings | Not an India model, so check before ordering |
| Redmi Note 9 Pro | Different phone | Has its own page, see below |
The listings are not a maker document. If your old pack says BN54, trust the label in your hand. If it says something else, trust that label too.
Note 9 and Note 9 Pro are two phones
This is the commonest slip at the counter. A buyer says "Note 9 battery" and the pack handed over is meant for the Pro. The two phones look alike in size and are often sold side by side, yet each has its own battery list.
The Pro and its code are explained on the Redmi Note 9 Pro battery page, and the neighbouring code is on the BN53 page. Do not swap one for the other because the capacity figure looks close. A pack with a near capacity but a different code may not fit the connector or the frame.
One owner walked in wanting a pack for his Note 9 and was shown one from the Pro rack. The technician opened the phone, read BN54 on the old sticker, and ordered that code instead. The rack label carried only two words and nothing more.
Rated and typical capacity of a BN54 pack
Adverts and listings use the 5020 mAh figure, which is the typical value. On the sticker, Xiaomi packs often show a rated number that is a little lower. Nobody has confirmed that rated number for BN54, so check the label on the physical battery you own and read it there.
To get energy in watt hours, you need the voltage as well. Multiply the mAh figure by the volts, and then divide the result by 1000. Just as an example, 5020 mAh at 3.85 V works out to about 19.3 Wh. The true voltage is printed on your own label.
Do not treat mAh as the whole story for battery life. Screen size, brightness, network signal and which apps stay open decide how long the phone lasts. For other phones of about this size, see the 5000 mAh phones page.
Checking BN54 before money changes hands
Searching a phone name gives a guess. The sticker gives the answer. Use the steps above, and keep three facts together when you ask for a pack: the code, the exact phone name and the capacity on the old label.
- Say the full phone name, not just "Note 9".
- Ask for the code
BN54in writing or on a photo. - Place the replacement next to the removed pack and compare connector and shape before anyone fits it.
If the old pack is too swollen or damaged to read, ask the service desk to look the code up from the phone's model number rather than guess.
Look-alike Redmi codes that get confused with BN54
Many Redmi packs differ from BN54 by a single character. Printing is small, and a worn sticker makes 3, 4 and 5 hard to tell apart. When in doubt, open the page for that exact code instead of assuming a share.
- BN53 is the nearest number and belongs to a different phone line.
- BN5R has a letter in the last place and is a different pack.
- BN56 is another close number with its own phones.
Every code in this family sits in the Redmi battery model list, which is the best place to start if your sticker shows something else.
Signs that a BN54 pack is tired
| Note 9 sign | What drives it | BN54 move |
|---|---|---|
| Percentage falls quickly after a full charge | Worn cell after long use | Do a battery check and book a replacement if it fails |
| Phone switches off with 15 to 30 percent left | Cell cannot supply sudden power | Get the cell tested at a service desk |
| Screen lifts or back cover gaps appear | Swollen cell | Leave it uncharged and go to a service centre |
| Phone feels warm while idle | Background apps or a faulty pack | Restart and remove the case, then recheck |
On a Note 9, apps and poor signal can look like a weak pack, so read why a phone loses charge so fast before blaming the cell. If the problem stays, follow the steps on the battery health check page and then choose.
A pack that bulges, runs warm or leaks can catch fire. Switch the phone off, do not charge it, do not press the pack, and keep it clear of heat until a service centre has looked at it. Low-priced copies that claim far more than 5020 mAh are a bad sign, so match the code and weight.
Fitting a new BN54 pack
Phones of this kind have glued backs, so opening them is work for a professional. Visit the maker's authorised service centre or a shop with a good name locally, and let them compare BN54 with the old sticker.
Once the replacement is in your hands, look at these points:
- It weighs close to the old one.
- The print is sharp and carries batch details.
- Its mAh claim is near 5020, not far above it.
Further tips are in the battery replacement guide. After the swap, keep the original charger in use and avoid leaving the phone plugged in within a hot room.
Frequently asked questions
Which phone uses the BN54 battery model name?
Most listings match BN54 to the Redmi Note 9, Redmi 9 Prime and POCO M2, sold as 5020 mAh typical. Ask the technician to read the code off your old pack to be sure.
What is the Redmi Note 9 battery model name?
Listings give BN54 for the Redmi Note 9. Do not confuse it with the Redmi Note 9 Pro, which is a different phone with its own battery code.
What is the POCO M2 battery model?
Most listings show BN54 for the POCO M2 as well. The phone is close to the Redmi 9 Prime, but check the label before ordering.
How many mAh is a BN54 battery?
Spare listings give 5020 mAh typical. The rated number printed on the pack can be slightly smaller, so go by your own label.
Is BN 54 the same as BN54?
Yes, the gap is just a typing habit. The printed code is BN54 with nothing between the letters and digits.
Can I use BN53 instead of BN54?
No, treat them as separate. The two codes belong to different phones, and a near capacity does not guarantee the same fit. Insist on the identical code and connector.