2
LITERATURE REVIEW
The integration of Internet of Things (IoT)
technology with battery management systems (BMS)
has gathered significant attention in recent years to
monitor and control vital parameters of batteries in
real time. This section will provide a quick overview
of the available research papers on battery monitoring
and SOC and an overview of its applications. Paper
(Ahmed et al., 2021) demonstrates the coulomb
counting method to estimate the SoC of a lead-acid
battery used with a photo voltaic system. It also
monitors the charging and discharging process using
Blynk IoT and operates a relay in case of
overcharging/discharging by continuously
monitoring the SOC of the battery.
The research paper (Chen et al., 2024) by
Gozuoglu presents a low-cost electronic dummy load
integrated with IoT capabilities. The system
accurately monitors the state of charge (SOC) and
state of health (SOH) of lithium-ion batteries using
IoT technology, offering enhanced monitoring and
remote access. The paper (Gozuoglu, 2024) by Chen
et al. explores an IoT architecture for battery
monitoring in power substations. The system provides
real-time monitoring and intelligent maintenance
management, demonstrating its effectiveness in a 110
kV offshore substation.The paper's authors (Insia,
2023) focus on monitoring battery health at charging
stations. The system uses IoT to provide real-time data
on battery performance, improving the efficiency and
safety of charging processes.
The technical paper (Lee et al., 2022) investigates
the application of IoT in renewable energy storage
systems. The study highlights the benefits of real-time
monitoring and data analytics for optimizing battery
performance and lifespan. The authors of the paper
(Patel et al., 2021) presented a system designed for
industrial battery monitoring. The IoT-based solution
offers continuous monitoring and predictive
maintenance, reducing downtime and maintenance
costs. The paper (Syafii et al., 2024) by Ahmed et al.
explores the integration of IoT with smart grids for
battery monitoring. The system provides real-time
data on battery status, enhancing grid reliability. The
research work presented in the above papers mainly
uses low-cost microcontrollers such as
Arduino/ESP32 microcontrollers to perform real-time
monitoring, which has limited data storage and control
capability. Hence, the research work presented in this
paper utilizes an advanced microcomputer, Raspberry
4, which can easily integrate with IoT technology and
log real-time data using the Excel tool.
3
BATTERY MANAGEMENT
AND STATE OF CHARGE
ESTIMATION
A Battery Management System (BMS) is an
embedded system that supervises the operation of a
rechargeable battery, ensuring its safe and efficient
use. It monitors various parameters such as the state
of charge, State of health, voltage, and temperature of
individual cells within the battery pack. It also
balances the charge across cells and protects against
overcharging, overheating, and short circuits. A BMS
also extends the battery's lifespan and enhances its
performance. Additionally, it provides critical data
for optimizing battery usage and maintaining overall
system reliability.
A crucial parameter in BMS is the State of Charge
(SOC), representing the remaining capacity of a
battery as a percentage of its total capacity. It
indicates how much charge is left in the battery, with
0% meaning fully discharged and 100% meaning
fully charged1. SoC is essential for predicting battery
performance and lifespan and helps manage energy
usage efficiently. Various methods, such as voltage-
based measurements and coulomb counting, estimate
SOC. Accurate SoC measurement is vital for
applications like electric vehicles, which function
similarly to a fuel gauge, providing users with real-
time information about their battery's status.
The following subsections briefly discuss the
battery management system and State of Charge
estimation.
Figure 1: Functionalities of Battery Management System.