Most spare part listings link the bn5f battery model name to three phones from the Xiaomi group. These are the Redmi A2, the Redmi A2+ and the POCO C51. The listed pack has a Li-ion polymer cell and a typical capacity of 5000 mAh. Redmi and POCO both belong to Xiaomi, so the BN letters tell you only the maker group and not a single handset.
Most people reach this page by typing "redmi a2 battery model" or "bn 5f" with a space. The code is printed on a sticker on the pack itself. These phones have sealed backs, so a technician has to open one before anyone can see that sticker. If you already hold an old pack, read the sticker first. If you only have the phone, use the steps below to be sure before you order anything.
Quick facts
Step by step
Write down the phone name from the box or settings
Open Settings, then About phone, and note the device name. If you cannot find it, type about in the Settings search bar.
Separate A2 from A2+ and from older A-series phones
Check for the plus sign in the name. The Redmi A1 and the Redmi A2 are different phones, so do not treat them as one when you order.
Let the technician read the sticker on the old pack
With the back open, look for
BN5Fprinted beside the capacity and voltage. Ask for a picture of it before the old pack is discarded.Compare the new pack with the old one side by side
The code, the connector end and the outline should match. Weight should also be close to the old pack.
Test after fitting
Charge fully once, then watch the phone for a day. Unusual heat or a quick drop in charge means the pack should go back for checking.
Phones that use the BN5F battery model name
Spare part listings give the same three phones for BN5F. The Redmi A2 and Redmi A2+ share one body, and the POCO C51 is a close relative of the Redmi A2, which is consistent with a shared battery. Treat the table below as a starting point, and trust the sticker on your own pack over any list.
| Phone | Match status | Note |
|---|---|---|
| Redmi A2 | Matched by listings | 5000 mAh typical |
| Redmi A2+ | Matched by listings | Plus version of the same phone |
| POCO C51 | Matched by listings | See the POCO C51 battery page for its own details |
| Redmi A1 | Not confirmed | Different phone, read the label |
| POCO C50 | Not confirmed | Looks similar, read the label |
One listing also names an unrelated phone from a much higher range for this code. That looks like an error, so ignore it and do not order on that basis.
Redmi A2 battery model: how to confirm it before you order
The search "redmi a2 battery model" has a short answer, which is BN5F according to most listings. The risk is in the details. A phone sold as A2 and a phone sold as A2+ can look the same from the front, and a pack meant for another budget Redmi can look the same too. Take five minutes and confirm three things: the phone name, the code on the old sticker and the connector.
The phone's own model number is also worth noting. You can find it in About phone or printed on the box. Give it to the seller or technician along with the phone name, because regional versions can carry different numbers and a model number helps them check the right pack.
Shoot the old sticker with the flash on and tilt the pack a little. Glare hides small letters, and a slight tilt removes it.
A general method that works for any phone is laid out on the page about finding the battery model name of any phone.
Rated and typical capacity of BN5F
Adverts for the phone and many spare part listings print 5000 mAh. That is the typical capacity. The rated (minimum) number on the pack is usually somewhat lower, and your own sticker may show both. Note which one you are reading, because a seller can quote the bigger number and leave out the smaller.
For energy, take the capacity times the voltage, then divide by 1000. As an example, at about 3.87 V, 5000 mAh gives about 19.4 Wh. Check the voltage on your own label, as it can differ a little. A pack close to the typical figure is normal. A pack that claims 6000 mAh or more for this phone cannot be honest, because the space inside the phone is fixed.
Do not expect the capacity alone to decide how long the phone lasts. Brightness, signal strength and heavy apps matter as much. If the phone drains quickly even with a good pack, go through the notes on why a battery drains fast first, since the fault may not be the cell.
BN5F, BN5R and other codes that get mixed up
Entry-level Xiaomi group phones share a 5000 mAh class, so counter staff often hand over the wrong pack by size alone. The code is the only safe test. BN5R sits close to BN5F in spelling and capacity, but it has its own phone list, so see BN5R for that. Another near neighbour is BN5D, which also has its own phone list.
- The letters F, R and P look alike on a worn sticker. Read slowly under a bright light.
- A pack with the same mAh but another code may arrive with a connector or outline that does not line up.
- "Compatible with Redmi A2" is not the same as the code BN5F. Ask for the code in writing.
The whole family of codes is laid out in the hub for every Redmi, Xiaomi and POCO code.
A customer with a Redmi A2 was handed two packs, both marked 5000 mAh. One said BN5F and the other carried a different code with a similar print. The technician compared the connector on each with the old pack and found the second one sat half a millimetre off. Only the BN5F pack was fitted.
Signs the pack in your Redmi A2 is tiring
| Clue | Probable cause | Action |
|---|---|---|
| Percentage drops quickly within months of ordinary use | The cell holds far less charge than when new | Do a battery health check and book a swap if it is poor |
| Phone powers off while the screen still shows charge | A worn cell cannot supply sudden bursts of power | Ask the service counter to test the pack |
| Back panel rises or the screen edge lifts | Cell is swelling | Unplug now and seek service the same day |
| Body stays warm even when the screen is dark | Damaged pack or an app running nonstop | Restart, remove the case, recheck |
Before you blame the cell, look at apps and mobile signal. The battery health check page explains how to judge it in plain steps.
A bulging back, heat at the edges, a leak or a chemical smell means the cell is unsafe. Unplug the charger, set the phone on a bare non-flammable surface away from curtains and paper, and do not squeeze it. Hand it to the maker's service counter the same day. Fake packs that print a far bigger mAh figure than the original are common, so insist on a pack that carries the BN5F code.
Fitting a new BN5F pack safely
The back of these A-series phones cannot be taken off by the user. Opening the body needs proper tools and a trained person. Going to the brand's own service counter is the safest choice, and a trusted repair shop comes next. Tell them the phone name and ask them to match BN5F against the sticker on the pack already inside.
When the replacement comes in your hands, inspect it before it goes inside:
- Hold both packs in your hand. A much lighter pack often holds less than it claims.
- Look at the print. Sharp letters and batch details are a good sign, and smudged print is a bad one.
- Check that the outline and connector are the same as the old pack.
The whole process, step by step, is covered under mobile battery replacement. A search for a "combo" usually means a pack sold with another part. You only need the battery, so ask for the code on its own.
Looking after the pack in a budget phone
Phones in this class often sit plugged in all night, and warmth together with many hours at 100 percent ages a cell sooner. Keep the phone on a hard, open surface while it charges. If it feels warm, slip off any thick case. Avoid long games while it is plugged in.
Pick a charger from the phone's own box, or any charger with an equal or smaller rating. If a cable turns hot near the plug end, throw it out and get another. At times the phone shuts down while the charge level still shows high. Restarting it and charging it fully may not fix this. When that happens, ask a technician to test the battery first, before paying for a new one. Keep in mind that a phone with no free storage runs slowly, and a fresh battery will not solve that.
Frequently asked questions
Which phone uses the BN5F battery model name?
Listings tie BN5F to the Redmi A2, Redmi A2+ and POCO C51, as a 5000 mAh typical pack. Your old battery's label will settle it.
What is the Redmi A2 battery model?
Listings give BN5F for the Redmi A2 and the A2+. A technician can verify this by reading the code printed on the pack after opening the phone.
How many mAh is the BN5F battery?
Shops list this pack as 5000 mAh typical. The number printed on your own pack is usually a bit lower, so check both values on it.
Is BN 5F the same as BN5F?
Yes, it is only a spacing difference in how people type it. The label on the pack carries the code as BN5F.
Can I use a BN5R battery in a Redmi A2?
Do not assume that. BN5R has its own phones, and a different code can mean a different connector. Ask for the exact code BN5F.
How can I tell a fake BN5F battery?
A fake pack often weighs less than a genuine one. Its printing looks smudged, and it shows no batch details. It may also boast a capacity far above 5000 mAh. Before you fit it, put the old pack next to it and compare them.