Bafang, the manufacturer of e-mobility components and complete drive systems, not only offers a full variety of drive systems – front, mid and rear motors – but also a complete range of batteries.
Distinguishing these from the competition is the voltage, it has said. Instead of opting for the standard 36 or 48V formats, Bafang’s engineers have decided to use a 43V battery design, for some “very good reasons.”
Earlier this year, it was announced that Bafang has expanded its battery collection for e-bikes with the introduction of two new models, BT F07.450.C and BT F08.600.C, offering 450Wh or 600Wh energy content respectively. They were launched during the Taipei Cycle Show, from 27th to 30th March.
Bafang has now outlined the advantages of the 43V battery design, compared to 36V and 48V systems:
Advantage 1: Heat efficiency
For batteries of the same capacity, the higher the voltage, the higher the working efficiency and the longer the range. When providing the same output power, the higher voltage leads to a lower working current, thus the battery and other components of the system produce less heat – and the efficiency will be improved accordingly.
When compared to the most commonly used 36V format, a 43V battery experiences just 69% of a 36V system’s heat loss. In terms of efficiency, a 48V battery is even better, at 59%, but has a disadvantage when it comes to space utilisation.
Advantage 2: Compact module arrangement
Depending on the capacity required, a 43V battery uses a 12S3P, 12S4P or 12S5P cell arrangement, resulting in a space utility of 75% for the complete package. Both competing formats are considerably less space-efficient.
A 36V battery’s 10S4P or 10S5P arrangement only manages 63% space utility, a 48V battery’s layout (13S3P, 13S4P or 13S5P) reaches no more than 65% – plus, that ‘high-end’ 48V battery leads to a very wide package which conflicts in particular with the requirements of state-of-the-art downtube integrated batteries.
“When you take both of these efficiency parameters into account, there’s a clear overall advantage to the 43V battery design,” said Sunny He, Bafang’s director and deputy general manager.
“And our latest battery options also have many additional advantages.”
Advantage 3: Safety
Users of Bafang’s new battery packs benefit from improved resistance against bad weather and high thermal stress – because the batteries are designed in accordance with the IPX6 standard, and their smart thermal management restricts any possible temperature rise to 20 degrees. But there are also many even more features and technologies implemented:
• Higher safety protection design: Bafang’s charging circuit is equipped with independent temperature control. All important functions are identified before charging. The charging circuit has been designed with six circuits for safety protection.
• Low voltage design: All batteries rely on the safer 4.1V full voltage level (instead of the standard 4.2V).
• Multi-stage failure safety protection: Bafang’s BMS (Battery Management System) uses two circuits to protect the chip against overcharge failure of the circuit and another two circuits to independently double-check for temperature
protection failure. A real-time calibration system checks for discharge overcurrent.
• Independent three-section fuses provide enhanced secure diagnosis of real-time MOSFET status, ensuring reliable on and off of the entire battery.
• Two-level safety mechanism protective design: After unlocking by key, there’s two-stage hook protection. A spring plate mechanism also facilitates attachment.
Advantage 4: Efficient manufacturing
To achieve its mission to deliver ever higher product value at lower manufacturing cost, Bafang has incorporated a flexible design, well suited for automatic production processes. The batteries’ standard core packs are assembled without any cables.
Reliability is ensured, and plastic parts can be made smaller, by taking full advantage of vibration welding and multiple insert-moulding processes.
Advantage 5: Easy handling and service
For the end consumer, the launch of a new charger line-up is good news. Both the CHG C01.3A and CHG C01.2A (with three and two amps charging current respectively) will fit all future Bafang batteries. And their 360-degree charging interface means “you can plug in even with your eyes closed.”
For product managers and dealers’ workshops, the following features are even more important:
• Free choice between CAN and UART communication protocols
• Software parameters can be updated with BESST (Bafang’s current service tool) – and in the future through cloud-based systems
• A resume recording function helps in cases of warranty issues, long term capacity monitoring and/or malfunction
Bafang will be attending Eurobike, in hall A1, booth 304.