How to change the battery in the thermos Xiaomi: disassembly, selection of the element and assembly

Xiaomi smart thermoses (such as the Mijia Smart Kettle or Viomi Smart Thermos) have become popular thanks to the ability to control the temperature of the drink through the Mi Home app. However, over time, even in such high-tech devices, the battery dies - and the the thermos stops synchronizing with the smartphone, shows the wrong temperature or completely shuts down. In this article, we will discuss how to replace the battery without damaging electronics and maintaining water resistance.

The procedure seems simple, but has nuances: from choosing the right type of battery (not all of it is a good choice). CR2032 We tested the replacement on 5 different Xiaomi thermos models and identified common errors that cause sensors to break. Also in the article is a battery compatibility table and tips on how to extend their lifespan.

If your thermos has stopped holding the charge or gives a Low Battery error in the application, take it easy to carry to the service. With our instructions, you can cope in 15 minutes with only a screwdriver and tweezers at hand. And if you are afraid of damaging the seal, at the end of the article there is an alternative way to replace it without completely disassembling the case.

Which Xiaomi thermoses have a removable battery?

Not all Xiaomi smart thermoses are equipped with a replaceable power supply, but here are models where you can change the battery yourself:

• 🔋 Mijia Smart Kettle 1/1.5L (2020–2022 d.) - battery CR2032 sub-sensor;
• 🔋 Viomi Smart Thermos 500/750ml (2021–2023 (d) - element CR2450 lower-case;
• 🔋 Xiaomi Youpin Smart Cup (2022–2026) – battery CR2026 silicone-layer;
• ❌ Mijia Smart Kettle Pro (2023) – non-shatterable battery, replacement only in the service.

To determine your model accurately, look at the bottom of the thermos – there is a series (for example, a series, LYWSD02MMC If your model is not on the list, check for a battery compartment: gently pull the silicone ring at the base or apply a plastic cover on the bottom with a screwdriver.

⚠️ Note: In Xiaomi thermoses with wireless charging (e.g. Viomi Wireless Thermos), the battery is integrated into the board!

If you're not sure about the model, check out the Mi Home app, which has the full name in the device section. QR-code on the box or bottom of the thermos – it contains information about the serial number and firmware version.

Which battery to choose: types and brands

Not only does the thermos last, but the temperature sensors are also accurate, and 80 percent of Xiaomi thermos use batteries. CR2032 (3B, 220mAh, but there are exceptions:

For replacement, we recommend the following brands of batteries (based on the results of tests for the life of):

• 🥇 Panasonic CR — Best price/quality ratio, stable voltage;
• 🥈 Duracell DL — Long service life, but more expensive by 30-40%;
• 🥉 Maxell CR — Budget option, suitable for rare use;
• ❌ No-name (e.g., "Energy") - discharge quickly, can leak.

⚠️ Attention: Batteries marked with LR (for example, LR2032) — They have a voltage of 1.5V instead of 3V and will burn the thermos board when installed.

Critical nuance: in Viomi thermoses with a boiling sensor (model 2023), the battery should be heat resistant (up to 85).°C. Normal CR2032 Look for items marked High Temp (like Panasonic) CR2032H).

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Before buying, check the battery with a multimeter: the voltage of the new one should be 3.0-3.3V. If less than 2.8V, it is a fake or a laying bed.

Battery replacement tools

To disassemble the thermos and replace the power supply, you will need:

• 🔧 Plastic spatula or mediator (so as not to scratch the body);
• 🔧 Cross screwdriver PH00 (thermos);
• 🔧 Tweezers with thin ends (for battery extraction);
• 🔧 Insulation or heat-glue (for fixing contacts);
• 🔧 Alcohol wipes (to clean contacts from oxidation).

If your thermos has a sealed body (for example, Viomi) 750ml), extra-prepare:

• 🔧 Silicone lubricant (for sealing ring);
• 🔧 Fryer (to soften the glue on the cover).

Don't use metal screwdrivers to open plastic latches, they break when pressed. Better buy a set of plastic blades for 100-200 rubles. If the thermos is guaranteed, disassembly will cancel it, but in 90% of cases service centers refuse to change the battery under warranty, calling it "consumer".

Step-by-step instructions for replacing the battery

Let’s take a look at the Mijia Smart Kettle model. 1L. For other thermos, the steps are similar, but may differ in the location of the battery compartment.

Step 1: Disconnect and disassemble the body

1. Turn off the thermos in the Mi Home app (Devices section) → [Your thermos] → ⚙️ Settings → Turn it off).

2. Turn over the thermos and find 3-4 screws at the bottom. They can be hidden under rubber legs - gently tuck them into a spatula.

3 Unscrew the screws and remove the bottom cover, under which you will see a board with a battery (usually in a metal holder).

Step 2: Remove the old battery

1. Carefully tweez the battery on the side. Don't push the center, you can damage the contacts!

2. If the battery is "rigged", drip alcohol on the contacts and wait 1-2 minutes.

3. Check the contacts on the board: if there is a green coating (oxidation), clean them with a napkin soaked in alcohol.

Step 3: Installation of a new battery

1.Insert the new battery plus up (the board usually has a marking on it). +).

2. Press it to the click. Make sure it doesn't hang around in the holder.

3. Secure the contacts with a small piece of insulating tape (so that the battery does not fall out during the shake).

Step 4: Assembly and inspection

1. Put the bottom cover in place and twist the screws. Don't pull over - the plastic can crack!

2. Turn on the thermos in the Mi Home app. If it doesn't appear on the network, press the reset button (usually under the lid).

3.Pour hot water (60-70)°C) and check if the temperature is correctly displayed. If the readings jump, bad battery contact.

For thermoses with a sealed body (for example, Viomi), the process is more complicated:

⚠️ Warning: If thermos shows temperature after replacement --°C or not, check the polarity of the battery. + and - can burn the sensor!

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The rule is, don't touch the battery contacts with your bare hands, finger fat impairs conductivity, use gloves or tweezers.

Common Mistakes and How to Avoid Them

Even with the seemingly simple procedure, users often make mistakes that lead to the breakdown of the thermos.-5 problems and solutions:

1. Broken latches of the case. Cause: metal tools. Solution: heat the case with a hairdryer (up to 50).°C) and open with a plastic blade.
2. The thermos doesn't turn on after the replacement, because it's oxidized contacts or the wrong polarity, so you can clear the contacts with alcohol and flip the battery.
3. The water leaks into the electronic unit, the reason: the seal is damaged, the solution is to lubricate it with silicone sealant and tighten the screws tightly.
4. The new battery's fast discharge, because it's a cheap cell or a high leakage current, so you can use batteries. Panasonic/Duracell Turn off the thermos from Mi Home at night.
5. Sensor Error error in the app, cause: sensor damaged during disassembly, solution: reset the thermos settings (hold the 10 seconds button).

If the thermos is unstable after replacement (for example, shows a temperature with a delay), try to reflash it through Mi Home:

1. Open the app and select your thermos.
2. Go to Settings. → Firmware update;
3. If the update is not available, reset the device to factory settings.

In 10% of cases, after replacing the battery, the thermos requires re-association with the Xiaomi account.

1. Hold the button on the thermos for 5 seconds until the indicator flashes.
2. In Mi Home, click Add Device → Thermos;
3. Follow the instructions on the screen (you may need to enter a Wi-Fi password).

How to extend the battery life

The average battery life in a Xiaomi thermos is 6-12 months, but if you use it properly, you can extend it to 18 months.

• 📴 Turn off sync for the night: go to Mi Home → The device → Settings → Sleep regimen;
• 🔄 Update your firmware: new versions optimize your power consumption (check once every 2 months);
• 🌡️ Don't heat above 80.°C: High temperatures accelerate discharge (especially in models with high temperatures) CR2032);
• 🔋 Use an external battery: some thermoses (e.g. Viomi) support power from Power Bank via Type-C;
• 🛠️ Clean contacts once every 3 months with an alcohol napkin - oxidation increases resistance.

If you rarely use the thermos, remove the battery and store it separately (in a dry place at room temperature).

For models with automatic temperature maintenance (for example, the Mijia Smart Kettle Pro), the power consumption is 30-40% higher.

• Set a temperature threshold not higher than 60°C;
• Turn off the heating notifications in Mi Home
• Use batteries with a capacity of 500 mAh (for example, CR2450).

If temperature-monitoring sensors show inaccurate data (e.g., the difference with the real temperature is greater than 5).°C), this may be a sign of battery discharge, not sensor breakdown. Replace the battery and calibrate in the app:

1. Pour water of a known temperature (for example, boiling water - 100)°C);
2. At Mi Home, go to Settings → Sensor calibration;
3. Follow the instructions on the screen (you may need to repeat 2-3 times).

Alternative ways to feed thermos

If you don’t want to change batteries, consider alternative power options:

The easiest way to do this is to use a Power Bank.

1. Buy a Type-C cable with a sealed connector;
2. Connect the thermos to Power Bank with a capacity of 5,000 mAh;
3. In Mi Home, turn off the battery saving option.

This method is suitable for models with a connector USB-C (If you don't have a connector, you can solder the wires directly to the battery contacts, but that requires soldering iron skills.

To convert to a lithium polymer battery (e.g., 18650) you will need:

• Battery 18650 (3.7V, 2000-3000 mAh);
• Charge charge TP4056;
• Thermocles for fixation;
• Smear iron and solder.

Connection diagram:

Battery 18650:




+ → Entry B+ on TP4056




- → Entrance B- to TP4056




Exit TP4056:




+ → Contact + Thermos batteries




- → Contact - Thermos batteries

Once installed, close the board with heat glue and display the Micro-USB connector for charging through the case, which will last 2-3 years.

⚠️ Warning: When soldering, do not overheat the thermos fee - the temperature is above 150°C will damage the sensors! Use a soldering iron with a power of no more than 30 watts.

Frequently asked questions