Wireless Battery Management System – Cost, Technology, And Effect

- May 18, 2020-

Lithium-ion is an excellent type of battery technology that is well renowned for its high-energy-density. This energy is capable of sustaining high-end machinery and technology. However, these batteries need a substantial amount of care if they are expected to operate under reliable terms and for an extended period. The capacity of these lithium-ion cells tends to degrade over time, and constant usage; therefore, every cell within the entire system needs to be managed appropriately. This would help keep the battery within a constraint SOC that is safe for both the battery and its users.

To provide sufficient power to a high-end invention such as the electric vehicles, many of these battery cells are required and configured in a long series generating as much as 1000V or even higher. The battery's BMS is required to operate at this too high voltage and reject the common-mode voltage effects. It is also expected to measure and control each cell in these strings differently and communicate necessary information from each cell in the entire pack to a central point for further processing.

Furthermore, operating a high-voltage battery pack in a vehicle or other HV applications imposes tough conditions like significant electrical noise as well as extreme temperatures. The BMS is expected to maximize the operating range, lifetime, safety, and reliability of the cells while reducing the cost, size, and weight. Advances in battery cell monitoring ICs have encouraged high-performance, increased the lifespan and reliability of various battery packs in the motor industry. Wireless BMS promises and claims to improve better the safety and reliability of the entire battery system in the world.


How much does a wireless battery management system cost?

The wireless BMS is just a concept that hasn't been fully implemented yet, nor has the prices for retail stock been announced. However, since it contains fewer components than the wired version, it is expected to cost lower than the wired BMS.


How is the technical development of the wireless battery management system?

In a wireless BMS, each module is usually interconnected through a wireless connection rather than a CAN Bus able or an isospin twisted pair at times. Modern technology today is demonstrating one of the industry's first wireless battery management system. This theory is mainly made for the automobile industry. It aims at replacing the traditional wired connections that exist between the battery packs and battery management systems.

The idea of a fully wireless BMS vehicle represents a massive breakthrough that offers the industry an opportunity for improved reliability, lower costs and reduced wiring complexity that were used in sizeable multicell battery packs designed for electric vehicles. Manufacturers are tasked at ensuring that both electric and hybrid vehicles are safe and reliable to drive in public. Advanced technology looks to increase the safety and reliability of battery monitoring ICs. This would help identify and work on the potential mechanical failures associated with connectors, cables, and wiring harnesses in high-end applications.


Up to date, the metal, as well as high-EMI surroundings in vehicles, were thought to be inconvenient for a wireless BMS to be reliable. However, through the efficient use of both path and frequency diversity to facilitate wireless messages around various obstacles and mitigate the interference. Research has shown that wireless networks tend to deliver more than 99% reliable data transmission in their harsh environments. They deliver all the reliability of the wires. They tend to eliminate mechanical connector failures, and this makes the wireless BMS concept a promising success of wireless technology.

Wireless BMS is capable of improving the overall system reliability and simplify the designs of automotive BMS. All in all, this wireless technology has proven to be more efficient when incorporated into fully functional systems such as the BMS.


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What is the effect of using a wireless battery management system?

The wireless battery management system provides the following advantages:

1.Low cost

There is a significant reduction in the cost of a battery pack because of the reduced number of components used, like wire-harness, connectors, protective cases for BMS boards, and isolators. The lowered costs make it easier for manufacturers to focus on more efficient battery packs that would provide substantial energy densities.

2.Reliability

Highly powerful wireless data communication, together with a reduced number of failure points, can improve the overall system's reliability. Furthermore, perfect isolation of high voltages provided by these wireless communications makes sure that there is maximum stability in transient and peculiar operation conditions.

3.Accurate Diagnosis

An in-built current sensor on each cell of the battery enables the early detection of internal short circuits on cells connected in parallel.

4.Productivity

The process taken to imbed the slave BMS modules into the cells of the battery can be fully automated. This would help eliminate the manual process of pack manufacturing as well as maintenance; thus, further lowering the manufacturing costs. Doing this also paves the way for a smaller and much lighter battery pack. Aso, wireless communication incorporated in the BMS provides more flexibility in modularization of the battery pack design.

5.Intelligibility

Each battery cell contains an in-built flash memory located on the slave BMS module. Cell ID and its usage history, together with other useful information,

can be stored. The cell history information can be later used for future applications like battery secondary-use.

6.Redundancy

With a wireless BMS, one can easily add a secondary communication channel useful for fault-tolerant design. In a wired BMS, one would require a separate set of wire-harness for them to achieve the same level of redundancy as the wireless version. One can also use the wireless BMS channel as a secondary to the conventional wired channel for various redundancy purposes. This provides many flexible design options to the manufacturers of the battery packs.

Final words

The world is revolving around wireless technology as experts have found a substantial amount of benefits that come with switching up to wireless devices. The BMS is also affected as the success of the future depends on whether we can adequately integrate this unit into our life.