Installation of an additional battery on the Xiaomi electric scooter: a complete guide with schemes and nuances

Xiaomi scooters are some of the most popular vehicles in the city, but their main drawback is limited range. 2 Xiaomi 4 Ultra rarely overcome more 50-60 km on a single charge, and budget versions (Xiaomi) 1S, Xiaomi Essential is already being discharged 20-30 The solution to the problem is the installation of an additional battery that can increase the mileage in the 1.5-2 But this process requires not only technical skills, but also an understanding of the electrical circuitry of the scooter.

In this article, we will analyze all the stages of modification: from choosing a compatible battery to setting up. BMS (Battery management systems) and testing. You will learn what errors lead to overheating of the controller or rapid wear of batteries, how to solder wires properly so as not to burn the board, and which models of Xiaomi scooters are best suited to upgrade. If you’ve never worked with lithium-ion batteries, start with a theory: an incorrect connection can cause a fire or the entire scooter to fail.

We won’t talk about “universal solutions” – each Xiaomi scooter has a unique power scheme, and what works on Xiaomi. M365, So this article is built as a step-by-step manual, taking into account specific models and their features. Ready to increase the mileage of your scooter!

1. What additional battery to choose for Xiaomi: types and characteristics

The first and most important step is to choose a battery, which not only increases mileage, but also makes it compatible with the scooter controller, safe operation and lifespans important.

Battery type:

• 🔋 Li-ion is the most common variant, lightweight, high-energy, but sensitive to overheating and deep discharge.
• 🔋 Lithium polymers (LiPos) are more compact and lightweight, but require a mandatory BMS It's also mechanical damage protection, often used in homemade assemblies.
• 🔋 Lithium-iron-phosphate (LiFePO4) — Safest and most durable (up to 2000 cycles), but heavier and more expensive.

Voltage and capacity:

The critical thing here is that the voltage matches the scooter's native battery. Most Xiaomi models are powered by a battery. 36V (10S configuration) or 48V (13S). For example:

• Xiaomi M365, Xiaomi 1S, Xiaomi Essential — 36V.
• Xiaomi Pro 2, Xiaomi 3, Xiaomi 4 Ultra — 48V.

Choose the capacity based on the desired mileage. M365 capacitance 7.8 Ah (280 Additional battery per battery 10 Ah will increase the range by about 30-40%, 20 Ah, almost in 2 But remember, the bigger the capacity, the heavier the battery is (10 Ah ≈ 1.5-2 kilogram).

Form factor and anchorage:

Additional battery can be installed:

• 🛴 Inside the standard compartment (replacing the native battery with a more capacious one) – suitable for Xiaomi M365 Xiaomi 1S.
• 🛴 Outside on the frame (in a bag or special fastener) - a universal option, but requires protection from moisture.
• 🛴 In the trunk or under the seat (if the scooter is modified).

Recommended battery models for Xiaomi:

⚠️ Warning: Never use batteries from laptops or powerbanks! they are not designed for high discharge currents (15-25A), It's going to cause an electric scooter to overheat, to swell or to ignite.

2. Tools and materials: what will be needed for installation

Before you start, prepare everything you need, save on tools or materials can result in short circuits or damage to the controller.

Main instruments:

• 🔧 Stolen iron (power) 60-100W) sluggish Sn60Pb40.
• 🔧 Multimeter to check voltage and resistance.
• 🔧 Thermal shrink tube (diameter) 3-10 mm) for insulation of compounds.
• 🔧 Pieces and strippers for wire sweeping.
• 🔧 Screwdrivers (cross, flat, torks) T20/T25 scooter).

Connection materials:

• 🔌 Power wires with a cross section of not less than 2.5 mm2 (for currents up to 20A).
• 🔌 Connectors XT60 or XT90 securely couple batteries.
• 🔌 BMS-charge (if not included with the battery) 36V — 10S, for 48V — 13S.
• 🔌 Double-sided scotch 3M or mounting clamps for battery fixation.

Additional accessories (optional):

• 🛡️ Thermopaste to improve heat removal from the controller.
• 🛡️ Waterproof bag (if the battery is installed outside).
• 🛡️ Voltmeter for monitoring charge (can be built into the handle of the scooter).

⚠️ Warning: If you use a soldering iron for the first time, practice on unnecessary wires. Poor soldering is the main cause of overheating contacts and loss of power.

Disassembly of the scooter and access to the regular battery

To connect the extra battery, you have to get to the battery and the controller, and the disassembly process varies from model to model, but the overall circuitry is the same.

Step-by-step instructions for Xiaomi M365/1S/Pro 2:

Features of other models:

⚠️ Warning: On some models (Xiaomi Pro 2), the controller is closed with heatpaste. If you disconnect it, be sure to apply a new paste when assembly, otherwise you risk overheating.

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Before disassembling, take a picture of the location of all the wires and connectors on the phone, which will help to properly assemble the scooter back and avoid connection errors.

Schemes for connecting an additional battery: in parallel or sequentially?

There are two main ways to connect the second battery: parallel and sequentially, depending on the voltage and the controller of your scooter.

Parallel connection (recommended for most models):

Used when the battery voltage is the same (e.g. two batteries) 36V batteries. in this case:

• 🔋 Capacity folds (10 Ah) + 10 Ah = 20 Ah).
• 🔋 The tension remains the same (36V).
• 🔋 The controller does not require reconfiguration.

Scheme: Connect plus to plus, minus to minus through BMS-(Required!) Use the safety lock on the 30-40A plus-wire.

2.Sequal connection (for experienced only!):

It is used if you need to increase the voltage (for example, connect the second one). 36V battery-in 48V system). In this case:

• 🔋 The tension is building up (36V + 12V = 48V).
• 🔋 Capacity remains the same.
• 🔋 Reconfigure the controller or replace it! Xiaomi's standard controller is not designed for high voltage and can burn out.

Example of parallel connection scheme for Xiaomi M365 (36V):

The battery (+) ────┬──── BMS ────┬──── Controller (+)




│              │




Additional Battery (+) ─────┴ └──── Controller (-)

⚠️ Note: When connected in parallel, both batteries must be of the same voltage (the difference is not more than one) 0.1V). If one battery is discharged more, an equalizing current will occur when connected, which can damage the elements.

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Parallel connectivity is the safest and easiest way to increase mileage, and consistent requires modification of the controller and is only suitable for advanced users.

5. soldering and isolation: how to avoid short circuit

Good brazing is the key to safety and durability of the modification.

Preparation of wires:

• Clear the wires on. 8-10 mm stripper.
• Tin the ends solder (this will improve contact).
• Use a heat shrink tube before soldering - it will be impossible to wear it later.

Folding of compounds:

• Heat the soldering iron to 300-350°C.
• Soak up the wires quickly (no more). 3-5 seconds) so as not to overheat the insulation.
• For power wires, use a flux solder (for example, Sn60Pb40).

Insulation:

• After soldering, put on a heat shrink and warm it up with a hair dryer or lighter.
• For additional protection, wrap the connections with tape or use a silicone sealant.

Typical mistakes in soldering:

⚠️ Attention: If you are soldering BMS-charge, make sure it is designed for the maximum current of your controller (usually 15-25A). Cheap boards can not withstand the load and burn.

6.Tune in. BMS system testing

After the battery is connected, you need to check the work BMS (Battery Management System and calibrate the controller.

1.Verification BMS:

• Connect the multimeter to the exit BMS and measure the voltage. It should be in the nominal (e.g, 36V or 48V).
• Check the balance of the cells: on most BMS There's a connector to monitor the voltage of each can, and the difference between the cells should not be greater than 0.05V.

Calibration of the controller (if required):

On some models (Xiaomi Pro 2, Xiaomi 4) after installing an additional battery, the charge indication may be lost.

Test launch:

• Turn on the scooter and check the charge readings in the Mi Home app.
• Come on. 1-2 km at low speed, watching the heating of the battery and controller.
• If the scooter twitches or loses power, check the connections and voltage.

⚠️ Note: If the scooter does not turn on or flashes red after installing the additional battery, the protection is most likely triggered BMS. Turn off the battery and check:

• Polarity of connection.
• Voltage on each bank (possibly one cell discharged to zero).
• Safety lock integrity.

7. Frequent problems and their solutions

Even if you install it properly, you can have problems.

1. The scooter shall not be switched on after the battery is connected:

• 🔍 Check the safety lock (can burn in KZ).
• 🔍 Make sure that BMS activated (some models require initial charging).
• 🔍 Measure the voltage at the exit BMS — if 0V, charge-problem.

Rapid discharge of one of the batteries:

• 🔋 Possible cause is the imbalance of the cells, so you need to charge/discharge the batteries separately to the same voltage.
• 🔋 Check the resistance of wires – thin or long wires create a voltage drop.

3. The scooter is twitching or losing power:

• ⚡ The problem may be insufficient current. BMS. Check that the fee is calculated for 20A+.
• ⚡ The controller may limit power due to non-standard voltage (relevant for serial connection).

Overheating of the battery or controller:

• 🔥 Make sure the battery is not covered with a tight case (ventilation is needed).
• 🔥 Check the quality of soldering – poor contact leads to heat.
• 🔥 If the controller is warming, apply a heat paste and make sure the radiator fits tightly.

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If the scooter after the modification began to "dull" on the climbs, check the voltage under load. 30V (for 36V The solution is to use a battery with a higher discharge current (e.g. Samsung). 30Q instead 25R).

8 Operational Tips: How to Prolong Battery Life

The extra battery requires special care to last longer.

Proper charging:

• 🔌 Charge the batteries at the same time (if they are connected in parallel).
• 🔌 Do not leave on charging more than 8 hours – this reduces the life of the battery.
• 🔌 Use the original RAM or similar current (1.5-2A).

Storage conditions:

• 🏠 Keep the scooter at 40-60% charge if you do not use it for more than a week.
• 🏠 Storage temperature: 10-25°C (avoid frost and heat).
• 🏠 Recharge your batteries once a month to avoid deep discharge.

Operation:

• 🛴 Avoid the full discharge (optimally, charge at 20-30% leftover).
• 🛴 Do not load the scooter with maximum current for a long time (for example, towing or steep climbs).
• 🛴 After the trip, let the battery cool down. 10-15 minutes before charging.

Status monitoring:

• 📊 Use the voltmeter or Mi Home app to track voltage.
• 📊 Check the balance of the cells once every 3 months with a balancer.

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Life of lithium-ion battery — 300-500 To prolong it, avoid extreme temperatures and deep discharge. Proper operation can increase the resource of the system. 20-30%.

FAQ: Answers to Frequent Questions