Upgrade of the Bluetooth lithium battery protection board for folding electric bicycles

December 7, 2024
Latest company case about Upgrade of the Bluetooth lithium battery protection board for folding electric bicycles

Electric Bicycle Battery Upgrade


  • Switching to Bluetooth Lithium Battery Protection Board

1. Background

An electric bicycle owner made multiple upgrades to his newly purchased vehicle within just four months.
 
One significant upgrade was replacing the original lithium battery protection board with a Bluetooth-enabled
 
one. The initial battery was equipped with a 15A co-terminal lithium battery protection board and was labeled
 
as 48V, with 13 series-connected cells and a capacity of 20Ah. However, upon disassembly, it was shockingly
 
discovered that there was severe false capacity indication. The actual capacity was merely 48V and 10Ah,
 
consisting of 6 parallel-connected 18650 cylindrical lithium battery cells and 4 parallel-connected 2.5Ah battery
cells.

2. Reasons for the Upgrade

The original protection board had several drawbacks. It lacked the ability to
 
accurately display crucial information like the battery level. In contrast, the new Bluetooth protection board offers
 
enhanced functionality. It can precisely show the charging and discharging current as well as the accurate State
 
of Charge (SOC) level. This improvement in battery status monitoring empowers the owner to have a more in-depth
 
and intuitive understanding of how the battery is being used. It allows for better decision-making regarding battery
 
usage and charging schedules.

3. Installation Process and Precautions

The core task during the installation process was welding. Given that

this demands professional tools and skills, if one does not possess a high-power soldering iron, it is highly

advisable to seek the assistance of professionals. Incorrect handling due to a lack of proper equipment can

lead to damage of the battery cells, typically caused by excessive contact time during the soldering process.

4. Usage Effect

After the replacement with the Bluetooth protection board, the owner can effortlessly

connect via Bluetooth using mobile devices. This connection enables real-time access to vital battery information

such as the charging and discharging current and the SOC level. With this knowledge at hand, the owner can more

effectively manage the battery's usage. They can create well-planned charging and usage strategies, which not

only extend the battery's lifespan but also enhance the overall convenience and safety of using the electric bicycle.

This upgrade is a significant step towards optimizing the performance and longevity of the electric bicycle's battery

system.

  • What Are the Key Tasks Involved in Upgrading the Bluetooth Lithium Battery Protection Board of a Folding Electric Bicycle?


Chip Upgrade

 
  • Replace with High-Performance Chips:

Opt for more advanced Bluetooth chips, such as the KT6368A dual-mode chip. This can reduce costs and enable more functions. Additionally,
 
it allows for the development of modules with different designs to match the mainboard.
  • Upgrade the Main Control Chip:

If the performance of the main control chip of the protection board is insufficient, consider upgrading to a chip with stronger processing capabilities and more
abundant resources. This helps to improve the management precision and response speed of the battery.

Enhancement of Bluetooth Function

 
  • Improve Bluetooth Signal Strength:

If the Bluetooth signal is weak, it can be resolved by adding an external antenna. For example, solder the components at the antenna position of the Bluetooth

 

module to the side, disconnect the onboard antenna, connect the antenna socket, and attach an antenna with an IPEX interface.
  • Optimize Bluetooth Connection Stability:

Optimize the Bluetooth communication protocol to reduce the probability of data transmission errors and interruptions. This can be achieved by updating the firmware
of the Bluetooth module.

Upgrade of Battery Management Function

 
  • Enhance Protection Precision:

Replace with high-precision voltage and current detection chips to more accurately monitor the charging and discharging status of the battery. This prevents
 
overcharging, overdischarging, overcurrent, and other situations, thereby extending the battery life.
  • Add Equalization Function:

The active equalization technology can keep the power of each cell in the battery pack consistent, improving the overall performance and cycle life of the battery pack.

Improvement of Safety Performance

 
  • Enhanced Over-temperature Protection:

Incorporate more sensitive temperature sensors and a more comprehensive over-temperature protection mechanism. When the battery temperature is too high,
 
promptly reduce the charging and discharging current or stop charging and discharging to prevent safety accidents such as thermal runaway.
  • Optimized Short-circuit Protection:

Optimize the response time and protection threshold of the short-circuit protection circuit. Instantly cut off the circuit when a short circuit occurs to protect the safety of
the battery and other equipment.

Upgrade Method

 
  • Online Upgrade (OTA):

If the protection board supports the OTA function, it can be connected to the Bluetooth of the protection board via a mobile APP or other devices. Download the latest

 

firmware program from the server and then upgrade according to the prompts without disassembling the protection board.
  • Offline Upgrade:

If OTA is not supported, the protection board needs to be disassembled from the electric bicycle. Use a professional programmer or burning tool to burn the new
firmware program into the chip of the protection board.