Dual Battery System Research Articles

Three-Port Converter With Leakage Inductance Energy Recycling for High Step-Down Applications

An emerging revolution in electric vehicles (EVs) is rapidly taking over the traditional fossil fuel vehicle market. Given its safety features and user-friendliness, the dual battery system (DBS) has been adopted in various EVs. A step-down three-port converter is essential for the DBS to supply low-voltage auxiliary power in EVs. In this paper, a novel high step-down three-port converter (TPC) is proposed by integrating the tapped-inductor technique and a buck converter for fulfilling the requirements of high step-down power conversion from sources to load with a reasonable duty cycle. It can also achieve independent power transfer among three ports. In addition, the energy stored in the leakage inductance of coupled inductor is recycled, with voltage spikes reduced across the switches. Finally, an experimental prototype is built to verify the theoretical analysis, with a main battery of 300 V, auxiliary battery of 48 V, load voltage of 24 V, and rated power of 300 W. The highest efficiency reached is 96.6%.

Lifespan-prolonging Dual Battery System Online Operation Scheduling for In-city Drone Delivery

Lifespan-prolonging Dual Battery System Online Operation Scheduling for In-city Drone Delivery

Complete Targets Coverage in Energy-Harvesting IoT Networks With Dual Imperfect Batteries

This paper studies the complete targets coverage problem in a novel and practical context: sensor nodes operating in an Internet of Things (IoT) network that have a dual-battery system with non-ideal properties. Specifically, sensor nodes have batteries that cannot be charged and discharged simultaneously. Also, sensor nodes must fully discharge/charge a battery before it is charged/discharged again. We outline a Mixed Integer Linear Program (MILP) and use it to optimize the activation schedule of sensor nodes. Its objective is to maximize complete targets coverage lifetime. We also propose a heuristic solution named Battery Switching Aware Algorithm (BSAA) to solve large problem instances. Simulation results show the performance of BSAA achieves approximately 98% of the coverage lifetime of MILP. In addition, equipping sensor nodes with a dual battery system prolongs the coverage lifetime by up to 70.2%.

Dual Battery Control System of Lead Acid and Lithium Ferro Phosphate with Switching Technique

The increase in electric vehicles needs to be supported by the existence of reliable energy storage devices. The battery, as an energy storage system, has its advantages and disadvantages. The combination of different battery types is chosen since the battery is one of the energy storage systems with mature technology and low life cycle cost. A solution that can be proposed to cover the weakness of each battery is the use of the Dual Battery System (DBS). In this project, a dual battery control system with a combination of Valve Regulated Lead Acid (VRLA) and Lithium Ferro Phosphate (LFP) batteries was developed using the switching method. Battery selection switching is determined by the specification and operational set point of the battery used. The experimental testing was carried out. The result of the research conducted showed that the current sensor accuracy was 83.75% and the voltage sensor accuracy was 94.25% while the current sensor precision value was 64.91% and the voltage sensor precision was 99.74%. The use of a dual battery system can save energy in a VLRA battery compare with a single VLRA battery by up to 68.62%, whereas in LFP battery by up to 29.48%. This means it gives the advantages of longer distances of traveling in electric vehicles.

Centralized Q-Learning based Routing in EH-WSNs with Dual Alternative Batteries

Energy harvesting wireless sensor network (EH-WSN) uses a large number of sensor nodes to conduct environmental perception, data collection and data transmission through wireless links. However, the battery capacity of traditional energy harvesting wireless sensor is limited. In this paper, a kind of energy collection wireless sensor of dual-battery system is studied, and a centralized energy-aware routing algorithm based on reinforcement learning is proposed. Considering the energy of the overall link, each source node chooses a good path at the beginning of data transmission. After all the data is transmitted to the sink node, it selects the path according to the whole network state, and learns several times until it finds the best path choice. The simulation results show that the end-to-end delay of this protocol is lower than that of random packet forwarding.

Rule Based Coordinated Control of Domestic Combined Micro-CHP and Energy Storage System for Optimal Daily Cost

This paper presents a novel control algorithm for optimising operational costs of a combined domestic micro-CHP (combined heat and power), battery and heat storage system. Using a minute by minute basic time-step, this work proposes a simple and computationally efficient rule based whole-system management, developed from empirical study of realistic simulated domestic electricity and heat loads. The CHP availability is considered in two binary states which, together with leveraging storage effectively, maximises CHP efficiency, and gives the algorithm increased real world feasibility. In addition, a novel application of a dual battery system is proposed to support the micro-CHP with each battery supplying just one of the distinctive morning and evening electrical load peaks, and thus inherently improving overall battery system lifetime. A case study is presented where the algorithm is shown to yield approximately 23% energy cost savings above the base case, almost 3% higher savings than that of the closest previous work, and 96.8% of the theoretical minimum cost. In general, the algorithm is shown to always yield better than 88% of the theoretical minimum cost, a ratio that will be considerably higher when real-world CHP limitations are factored into the theoretical minimum calculation.

Predictive performance estimation for a dual-battery system in mild-hybrid vehicles

Abstract. Continuously increasing requirements for on-board system performances lead to new topologies for the energy distribution in vehicles. One promising concept is the usage of a dual-battery system instead of the conventional lead-acid “starting lightening ignition” battery. As this system is not able to control the current share between the two batteries, its performance depends on the actual battery specific operating points.The initial conditions of state of charge, voltage level and temperature influence the current share and lead to a different voltage drop of the system. This paper yields to, the basic understanding of the current share between the two batteries. The conventional performance estimation method for standalone lead-acid batteries can no longer be applied to this system. Therefore, a new algorithm for the voltage drop calculation of the dual-battery system is proposed. Measurements at different temperatures, states of charge and voltage levels show the system behavior and prove the functionality of the algorithm.

Model-Based Analysis of a 12V Dual-Battery System for Design Optimization of Microhybrid Vehicles

12V microhybrid (MHEV) technology has potential to deliver 5-10% fuel economy improvement over traditional gasoline vehicles without adding excessive cost to the consumer. Parallelizing the traditional lead acid battery with a high-power lithium ion battery has the potential to enable critical microhybrid function such as regenerative braking. Enabling a low-cost passive connection between the lead-acid and lithium-ion batteries requires compatibility between the two batteries, including design factors such as battery size, resistance, and open-circuit voltage (OCV).In this work we have developed a dual-battery model that couples an electrochemical model of a lithium ion battery and an equivalent circuit model of a lead acid battery in order to perform design optimization of a passively-connected dual-battery MHEV system. We analyzed the dynamic responses of the two batteries upon high power charge and discharge pulses, with and without simulated vehicle accessory loads. The current split between the two batteries is explored in detail as a function of pulse characteristics, operating voltage, and accessory load. Finally, a simulated vehicle regulatory drive cycle, specifically the New European Driving Cycle (NEDC), is implemented for analysis of contributions of two batteries.

Electro-Generation of the Microbe Fuel Cell for Pyrite-MnO<sub>2</sub> in the Presence of <i>Acidithiobacillus ferrooxidans</i>

Pyrite was used to study the electro-generation both the sterile dual battery system and the microbe fuel cell for pyrite-MnO2in this paper. The Relationship between potential, work output, and current for pyrite in presence ofA. ferrooxidansand sterile, showed that the electro-generation trend enhanced in the presence ofA. ferrooxidansfor pyrite. The Evans graph for pyrite in presence ofA. ferrooxidansand sterile showed that with the increase of current, the output potential decreased. The dissolved metal ion in the presence ofA. ferrooxidansis nearly 12% higher than that in the absence ofA. ferrooxidans; the electro-generative quantity in the former is about 166% more than that in the latter; the transferred charge due to the bacteria is more than that of sterile dual battery process in the last stage of microbe fuel cell.

Analysis and Implementation of a Novel Bidirectional DC–DC Converter

A novel bidirectional dc-dc converter is presented in this paper. The circuit configuration of the proposed converter is very simple. The proposed converter employs a coupled inductor with same winding turns in the primary and secondary sides. In step-up mode, the primary and secondary windings of the coupled inductor are operated in parallel charge and series discharge to achieve high step-up voltage gain. In step-down mode, the primary and secondary windings of the coupled inductor are operated in series charge and parallel discharge to achieve high step-down voltage gain. Thus, the proposed converter has higher step-up and step-down voltage gains than the conventional bidirectional dc-dc boost/buck converter. Under same electric specifications for the proposed converter and the conventional bidirectional boost/buck converter, the average value of the switch current in the proposed converter is less than the conventional bidirectional boost/buck converter. The operating principle and steady-state analysis are discussed in detail. Finally, a 14/42-V prototype circuit is implemented to verify the performance for the automobile dual-battery system.

Automotive DC-DC bidirectional converter made with many interleaved buck stages

Interleaving technique is used in some applications due to its advantages regarding filter reduction, dynamic response, and power management. In dual battery system vehicles, the bidirectional dc-dc converter takes advantage of this technique using three-to-five paralleled buck stages. In this paper, we propose the use of a much higher number of phases in parallel together with digital control. It will be shown that this approach opens new possibilities since changes in the technology are possible. Thus, two 1000-W prototypes have been designed using surface mount technology devices (SO-8 transistors). An additional important feature is that due to the accuracy of the digital device [field-programmable gate array (FPGA)], current loops have been eliminated, greatly simplifying the implementation of the control stage

VRLA automotive batteries for stop&go and dual battery systems

The electrical power requirements for vehicles are continuing to increase and evolve. A substantial amount of effort has been directed towards the development of 36/42 V systems as a route to higher power with reduced current levels but high implementation costs have resulted in the introduction of these systems becoming deferred. In the interim, however, alternator power outputs at 14 V are being increased substantially and at the same time the requirements for batteries are becoming more intensive. In particular, stop&go systems and wire-based vehicle systems are resulting in new demands. For stop&go, the engine is stopped each time the vehicle comes to rest and is restarted when the accelerator is pressed again. This results in an onerous duty cycle with many shallow discharge cycles. Flooded lead–acid batteries cannot meet this duty cycle and valve-regulated lead-acid (VRLA) batteries are needed to meet the demands that are applied. For wire-based systems, such as brake-by-wire or steer-by-wire, electrical power has become more critical and although the alternator and battery provide double redundancy, triple redundancy with a small reserve battery is specified. In this case, a small VRLA battery can be used and is optimised for standby service rather than for repeated discharges. The background to these applications is considered and test results under simulated operating conditions are discussed. Good performance can be obtained in batteries adapted for both applications. Battery management is also critical for both applications: in stop&go service, the state-of-charge (SOC) and state-of-health (SOH) need to be monitored to ensure that the vehicle can be restarted; for reserve or back-up batteries, the SOC and SOH are monitored to verify that the battery is always capable of carrying out the duty cycle if required. Practical methods of battery condition monitoring will be described.

The impact of the new 36 V lead–acid battery systems on lead consumption

The production of vehicles utilizing 36V battery systems has begun with the introduction of the Toyota Crown. Other vehicles with 36V batteries are in the near horizon. These vehicles may contain single or dual battery systems. These vehicles will most likely contain valve-regulated lead–acid (VRLA) batteries. The battery systems developed to date utilize significantly more lead than conventional 12V batteries.This paper will evaluate the different proposed 36V battery systems and estimate the lead requirements for each of the competing systems. It will also project the penetration of and resultant increased lead usage of these new batteries into the future.

Vehicle electric power systems are under change!: Implications for design, monitoring and management of automotive batteries

New technical features, the demand for fuel economy, and the potential to reduce production and operational cost are leading to additional and more powerful electrical consumers and making the overall electrical demand in vehicles increase. Vehicle electrical architecture is performing an evolutionary change to improve the efficiency of production, distribution, control and storage of electrical energy in the vehicle. New battery designs with performance patterns designed for the new architectures are needed, and some of the new demands may even exceed the capability of lead/acid batteries. Single and dual battery systems offer a wide variety of applications when combined with intelligent means to keep the batteries in an appropriate operational window. Detection of state-of-charge (SOC) and state-of-health (SOH) is essential to help the battery to fulfil its role as a key element for vehicle functionality and safety.

Design options for automotive batteries in advanced car electrical systems

The need to reduce fuel consumption, minimize emissions, and improve levels of safety, comfort and reliability is expected to result in a much higher demand for electric power in cars within the next 5 years. Forecasts vary, but a fourfold increase in starting power to 20 kW is possible, particularly if automatic stop/start features are adopted to significantly reduce fuel consumption and exhaust emissions. Increases in the low-rate energy demand are also forecast, but the use of larger alternators may avoid unacceptable high battery weights. It is also suggested from operational models that the battery will be cycled more deeply. In examining possible designs, the beneficial features of valve-regulated lead–acid batteries made with compressed absorbent separators are apparent. Several of their attributes are considered. They offer higher specific power, improved cycling capability and greater vibration resistance, as well as more flexibility in packaging and installation. Optional circuits considered for dual-voltage supplies are separate batteries for engine starting (36 V) and low-power duties (12 V), and a universal battery (36 V) coupled to a d.c.–d.c. converter for a 12-V equipment. Battery designs, which can be made on commercially available equipment with similar manufacturing costs (per W h and per W) to current products, are discussed. The 36-V battery, made with 0.7 mm thick plates, in the dual-battery system weighs 18.5 kg and has a cold-cranking amp (CCA) rating of 790 A at −18°C to 21.6 V (1080 W kg −1 at a mean voltage of 25.4 V). The associated, cycleable 12-V battery, provides 1.5 kW h and weighs 24.6 kg. Thus, the combined battery weight is 43.1 kg. The single universal battery, with cycling capability, weighs 45.4 kg, has a CCA rating of 810 A (441 W kg −1 at a mean voltage of 24.7 V), and when connected to the d.c.−d.c. converter at 75% efficiency provides a low-power capacity of 1.5 kW h.

Optimum battery configuration for maximum utilization of photovoltaics

AbstractVarious photovoltaic (PV)‐powered battery storage configurations are analysed to determine if the percentage of available energy stored in the battery can be improved. Both deep‐cycle and shallow‐cycle lead‐acid batteries are considered. Computer simulation techniques are used to model the characteristics of the PV array, daily loads and environmental conditions. Three configurations were tested: one 60 ampere‐hour (Ah) battery, two 60 Ah batteries in parallel and two 60 Ah batteries that switch between the PV array and the load. Results show that the conventional PV‐powered configuration, where one battery is charged, wastes enormous amounts of energy by reaching a charged state while the PV array can still provide energy. A dual battery system enables the excess energy to be shunted into the battery under load while concurrently ensuring that one battery is constantly under charge until a full state of charge is achieved.

Testing Batteries for Vehicular Applications: III . Selection and Characterization of a Power Battery

The problem was to find an acceptable “power” battery (i.e., a high power density battery to deliver short time acceleration pulses) for an electric commuter vehicle concept powered by a dual battery system. A number of batteries were tested, both Pb‐acid and Ni‐Cd. The best battery was a Ni‐Cd aircraft starting battery. It could deliver 14 consecutive 1900W, 10 sec acceleration power pulses. It was calculated that about 180 lb of battery would be required for the particular power plant design envisioned. The high cost and scarcity of Cd militated against the use of a Ni‐Cd battery. The next best candidate was a Pb‐acid aircraft starting battery designed for high current drains for short time periods. It, too, delivered 14 consecutive 1900W, 10 sec pulses. In addition, it had sufficient energy capacity to provide some low speed range in the event of failure of the “base‐load” energy battery. It had a power density of 70 W/lb at an energy density of 2 Whr/lb. About 270 lb of this battery would be required for the “power” battery pack. A Delco‐Remy 2HN‐11A military battery was tested to yield design data for the power plant. From these data, a battery was designed which would fit into an available lightweight container. Prior to this, a 2HN‐11A modified battery was tested to confirm the design. Test results confirmed the designed capacities.Several of the design batteries were built. Each consisted of seven cells containing 11 plates per cell. One of the batteries was tested. It delivered 15 consecutive 2500W acceleration power pulses to 10.5V. It weighed 32 lb; hence, the entire power pack would weigh 256 lb. Since the 11‐plate cell performed so well, it was hoped that a 9‐plate cell might just deliver adequate power. A 27 lb weight reduction would be realized. However, it could not deliver adequate power when tested. Nothing could be obtained at 2500W. The voltage fell immediately below 10.5. In fact, only 1.8 min were obtained at 1900W.