The POCO C51 battery model name is BN56 in most replacement listings, with some packs sold under BN5F for the same set of phones. Xiaomi rates the C51 at 5000 mAh, which matches both.
A few sellers print BN5R in their titles for the C51 too, but BN5R is the code most listings give the Redmi A3. Where BN56 and BN5F listings conflict, trust only the label on your own cell.
Quick facts
POCO C51 battery model name in listings
Phones sold alongside the C51 with the same pack
Xiaomi often sells one phone under two names. The POCO C51 sits close to the Redmi A2 and A2+, and listings group it with the older Redmi 9A and 9C for battery purposes. In practice that means the replacement market for the C51 is large and full of generic packs. Look for a cell that names the C51 or the 9A by model and prints BN56 or BN5F clearly. A blank sticker or one that claims 6000 mAh is not a genuine part.
The Redmi A1+ also appears in some BN56 listings, which tells you how widely this pack was used across Xiaomi's entry phones.
Why one pack carries two codes
Xiaomi sometimes changes the cell supplier for a pack while keeping the size and connector. Sellers then list both codes together, as with BN56 and BN5F for the 9A and C51 family. That does not mean any BN code fits; it means these two have been sold as one part. Check that a replacement names your phone and one of these two codes.
Checking the code on a C51
Find the model number on the About phone screen first; one listing quotes MZB0EVCIN for an Indian C51. Once the back is off, the cell label is easy to read. If it says BN56 or BN5F with 5000 mAh, either listing will do. If it says something else, follow the label.
The C51 often ends up as a child's or a parent's second phone and spends long hours on a charger. If it has become warm all the time or the back has lifted, unplug it and get the cell removed instead of waiting for it to fail.
Battery life on the POCO C51
With a low power chip and an HD screen, a C51 in good health can run well over a day of light use. Charging at 10 W from empty takes around three hours. Why phones show two capacity figures is covered on our battery capacity page.
Replacing the battery
Xiaomi service centres handle POCO phones. Ask them to fit a genuine pack and keep the old one for recycling. The POCO, Redmi and Xiaomi code index shows related codes, and our battery replacement guide covers what to check after fitting.
Signs the C51 battery needs replacing
A C51 that once lasted a day and a half but now needs charging by dinner, or one that drops from 20 percent to zero in a few minutes, has a worn cell. The same goes for a phone that only works while plugged in. Rule out a misbehaving app first by checking which apps use the most battery in Settings. If no app stands out, the pack is the likely cause.
Frequently asked questions
What is the battery model of POCO C51?
Most listings give BN56, with some packs sold as BN5F for the same phones.
What is the POCO C51 battery capacity?
5000 mAh, charged at 10 W.
Is the POCO C51 battery the same as Redmi 9A?
Listings place both in the BN56 and BN5F family, but confirm the code on your cell.
Does BN5R fit the POCO C51?
Only one listing says so; most give BN5R to the Redmi A3. Do not order it without seeing it on your label.
How long does a POCO C51 take to charge?
With the 10 W charger in the box, about three hours from empty. Faster adapters do not speed it up much.