The question of what kind of power is required for the Xiaomi Smart Scale 2 scales often arises when the discharge indicator lights up or the device stops turning on. This is a popular smart scale model that, thanks to its accuracy and integration with the Mi Fit app (now Xiaomi Wear or Zepp Life), has become the standard in the category of affordable health gadgets. However, like any electronic device, they require a timely replacement of the power source for the correct operation of sensors and Bluetooth module.
It's important to note that confusion often arises from the similarity of model names and design features across generations. If you have the second version, also known as the Mi Body Composition Scale 2, you need to know the specific size of the batteries, which is different from the classic "finger" counterparts. A wrong battery can not only fail to work, but also damage the contact group due to mismatch of dimensions or voltage.
In this article, we will discuss in detail which batteries are suitable for your device, what is the difference between Xiaomi scale models, how to replace them correctly and what to do if the scales stop working even after installing new elements. We will touch on the technical nuances that will help to extend the life of the gadget and avoid common maintenance errors.
Type of power supply for Xiaomi Scale 2
The Xiaomi Smart Scale 2 (often labeled NUN4076GL or XMTZC05HM) uses AAA-type batteries, often referred to as "little finger" or "threes," which are cylindrical batteries that are thinner and slightly shorter than standard AAs, which are used in many other household appliances, and each battery has a standard 1.5 volt voltage.
The device operates from four such elements connected in series, which in total gives the necessary voltage for the operation of high-precision strain gauges and Bluetooth connections. It is important not to confuse this model with the first version of the scale (Mi Body Composition Scale 1), which had a glass platform with a mirror coating and was powered by four batteries. AA. The second version is visually different from the presence of a hidden LED-a display under glass that only lights up when weighed, while the first version had a more visible screen.
💡
For maximum measurement accuracy and long life, use only alkaline batteries from proven brands such as Duracell, Energizer or GP. Salt analogues can quickly discharge and flow.
When buying, pay attention to the labeling. The package or the battery itself should be labeled AAA or LR03 (for alkaline). If you see the R03 label, this is a salt battery, the resource of which in smart scales will be much lower. There are also battery versions of Ni-MH with a voltage of 1.2 Volts - their use is possible, but the scales can show a false discharge signal ahead of time due to the difference in voltage.
Differences in nutrition of different models of Xiaomi weights
Xiaomi's lineup of smart scales and the Mijia ecosystem has many models, and their power requirements differ. Understanding these differences is critical, because trying to set the wrong size can lead to mechanically stuck elements in the compartment or no contact. Let's organize the data by the main models so you can be sure of the choice.
The first generation of scales (Mi Smart Scale 1), which can often be recognized by the characteristic white or black glass and visible display, required 4 elements of type AA. These are larger batteries that will not physically fit into the compartment of the second model without disrupting the design. The second model (Mi Body Composition Scale 2), which is discussed in the article, moved to a more compact AAA, which made the platform thinner and sleeker.
There are also newer and more advanced versions, such as the Mi Smart Scale 2 (XMTZC02HM/NUN4017GL model) and the Mi Body Composition Scale 2 Pro. These devices often have an integrated battery that is charged via a Micro-USB or Type-C port located on the end of the device.
How to distinguish a model by appearance?
Below is a table that will help you quickly identify your device’s requirements based on its characteristics and the markings at the bottom:
| Model of the device | Type of element | Number (s) | Features |
|---|---|---|---|
| Mi Smart Scale 1 | AA (LR6) | 4 | Visible display, thicker body |
| Mi Body Composition Scale 2 | AAA (LR03) | 4 | Hidden LED, thin body |
| Mi Smart Scale 2 (XMTZC02HM) | Built-in Li-Ion | 1 | Charging via USB |
| Mi Body Comp Scale 2 Pro | Built-in Li-Ion | 1 | Charging through Type-C |
Step-by-step instructions for replacing batteries
The process of replacing the batteries in Xiaomi Smart Scale 2 is simple enough, but requires care so as not to damage plastic latches or contacts. Before starting the procedure, make sure you have 4 new AAA batteries on hand and possibly a small cross screwdriver, although you can often do without it.
Turn the scales down with the work surface. On the bottom of the device, you'll see the battery compartment cover. Depending on the specific revision of the case, it can hold on the latches or require the screw to be unscrewed. If the screw is present (usually closed with a sticker or in a recess), gently unscrew it. If there are no screws, find a notch for the finger and with a little effort, move the lid in the direction indicated by the arrow, or simply lift it.
☑️ Pre-replacement checks
Take out the old batteries. Pay attention to the direction of installation: there's always a plus diagram at the bottom of the bay. + And the downside is -- in Xiaomi Scale 2, the batteries are usually set in series, head to tail. Insert new batteries, polarity. Once installed, the lid should close tightly, without gaps. If the lid does not close, do not push, check that the batteries are installed correctly.
After replacement, turn on the scales by stepping on them briefly. The Mi logo or weight reading should appear on the display. If the device shows a dead battery symbol immediately after replacement, this can mean poor contact. Try turning the batteries slightly in the compartment or wipe the contacts with dry cloth.
Why the scales are not included after replacement
When you have installed new batteries, and the Xiaomi Smart Scale 2 is still unresponsive, it's not common, but there are a few technical explanations. The first thing to do is check the quality of the batteries themselves. Even new batteries may be defective or have expired. Try putting them in another device, such as a TV remote, to make sure they work.
The second reason is often oxidation of the contacts inside the device itself. If you've been using scales for a long time or previous batteries could leak, the contact plates could have oxide plaque that prevents current from flowing, in which case you need to clean the contacts carefully, and you can use a cotton swab dipped in alcohol or a special contact cleaner, but be sure to let the device dry completely before installing new elements.
⚠️ Warning: Never use water or wet wipes to clean the contacts inside the electronics. The liquid can get under the charge and cause a short circuit, which will permanently disable the scales.
Also, consider temperature: Lithium and alkaline batteries can temporarily lose capacity in extreme cold. If the scales were stored in an unheated room or brought from the cold, let them warm up to room temperature for 1-2 hours before turning on. A sharp temperature drop can also cause condensation inside the housing.
In rare cases, the problem is a software failure of the controller, so try to do a complete reset: take out the batteries, leave the scales in this state for 10-15 minutes, then insert the batteries again, which will allow the capacitors on the board to completely discharge and start the system again.
How to extend the life of the power supply
The Xiaomi Smart Scale 2 is an energy-efficient device, and one set of high-quality batteries is usually enough for 6-12 months of active use. However, there are a number of factors that can significantly reduce this time.
The main energy consumer is a Bluetooth module. If you often measure weight but don't sync with your smartphone, the scales still use up the charge to maintain standby and find connections. Try to open the Zepp Life or Mi Fitness app immediately after weighing in, so that the device quickly transfers data and goes into sleep mode.
Frequently "exciting" the scales also affects flow, so you don't step on them to check the charge or just like that. Each turn on is the cycle of the processor and the display. In addition, setting the scales on an uneven, soft surface (carpet, carpet) causes the strain gauges to work in an abnormal mode, trying to calibrate, which also consumes energy.
If you plan to not use the scales for a long time (for example, going on vacation for a month or more), it is better to remove the batteries from the compartment. This will prevent possible leakage of the electrolyte and ensure that the battery is stored for the next use.