Your Selections

Battery Packs
Show Only

Collections

File Formats

Content Types

Dates

Sectors

Topics

Authors

Publishers

Affiliations

Committees

Events

Magazine

   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Battery cell modeling for energy and power estimations in a battery pack applied to a HEV

Juliana C M S Aranha, Felipe Lima Marques, Thiago Chiachio CPqD
  • Technical Paper
  • 2019-36-0243
Published 2020-01-13 by SAE International in United States
In this paper we present the concept of cell battery modeling and its importance to the battery management system of a HEV. A review of possible equivalent circuits to model the battery electric behavior is made and we present the proposed equivalent circuit to this application. This model takes into consideration the temperature, current and state of charge conditions in which the battery is being used, without adding equations to state-space model. Then, we discuss the laboratory tests that need to be performed to provide information for the models. A test procedure is presented in 6 different scenarios. Finally, the results of the application of this methodology for a NMC battery cell are showed. The maximum RMSE found between real and estimated voltage by the model was 1.0041e-4. A state of charge estimation using this model showed a 1.995e-6 mean squared error.
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Balancing Strategy for a Battery Applied in HEV Based on Bi-directional Flyback Converter and Outlier Detection

CPQD – Research and Development Center in Telecommunications-Felipe L. R. Marques, Juliana C. M. S. Aranha, Fernando F. Padela, Maria de Fátima N. C. Rosolem, Raul F. Beck
  • Technical Paper
  • 2019-36-0242
Published 2020-01-13 by SAE International in United States
Dissipative cell balancing generates heat during its operation. Current techniques do not guarantee optimal balance of battery pack energy, requiring a high-cost Battery Management System (BMS) solution and wasting energy in the form of heat. Mild Hybrid Electric Vehicles uses the combustion engine to recharge the battery. Therefore, this feature requires a BMS balancing system capable of optimizing battery capacity and still be energy efficient. In this way, a non-dissipative balancing system would be interesting, especially if an algorithm works with the former non-dissipative balancing method, which efficiently determines which cells are unbalanced. In this paper, a methodology is proposed to perform non-dissipative balance of lithium-ion cells. This method considers which cells inside a certain range are considered balanced and cells outside this range are considered unbalanced. The range is given by the median of the cells terminal voltage summed with a threshold defined by experimental tests. Due the non-dissipative method presented herein is conceived through Flyback topology, the cells above this range are discharged and their extra energy is employed to charge the lowest…
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Innovative Fluid Allowing a New and Efficient Battery Thermal Management

TOTAL Marketing Services-Jonathan RAISIN, Nicolas CHAMPAGNE
  • Technical Paper
  • 2019-01-2259
Published 2019-12-19 by SAE International in United States
With the increasing availability of fast charging stations across the globe, tighter and tighter constraints are placed on electric vehicles batteries. In order to handle the thermal stresses induced during fast charging, the improvement of the existing battery thermal management systems has become key. This article presents an innovative thermal management system for batteries. The system consists of circulating a newly developed highly advanced dielectric fluid in direct contact with the electrochemical cells of the battery pack. Experiments on our dedicated bench test and numerical simulations are reported here demonstrating the performance of this system with fluids, i.e. its ability to efficiently regulate the temperature of the battery cells even under fast charging conditions and low flow rates. Consequently, this thermal management strategy could be implemented within the next generation of battery electric vehicle (BEV) using conventional pumping systems and lead to an improved battery lifetime and therefore a lower total cost of BEV ownership.
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Akasol packs industry-leading energy density into new battery design

SAE Truck & Off-Highway Engineering: December 2019

Bill Visnic
  • Magazine Article
  • 19TOFHP12_08
Published 2019-12-01 by SAE International in United States

Projecting the market for full-electric and hybrid-electric commercial vehicles will continue to expand, Germany-based lithium-ion battery specialist Akasol recently announced production-readiness of a newly-developed battery pack that sets an energy-density benchmark. The company's president also confirmed Akasol will build a manufacturing facility in the Detroit area targeted to begin production in mid-2020.

Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

How battery technology will drive truck electrification

SAE Truck & Off-Highway Engineering: December 2019

Alexander Schey
  • Magazine Article
  • 19TOFHP12_10
Published 2019-12-01 by SAE International in United States

The past three years have seen a major shift in the perception around electrified commercial vehicles, including trucks, driven by a variety of factors that have come together at this particular time. These factors include a growing awareness and acceptance of the impact of CO2 emissions on climate change and the dangers of diesel emissions-most notably highlighted by the Volkswagen emissions scandal-alongside a growing maturity and improved cost profile on electric vehicle (EV) technology. As a result, fleet owners and OEMs now consider e-trucks much more seriously.

Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Numerical Simulation of Battery Thermal Management Systems in Electric Vehicles

Pranav Vikas, Ltd.-Bharat Kumar Nuthi, Vijayaraghavan S, D. Govindaraj
  • Technical Paper
  • 2019-28-2481
Published 2019-11-21 by SAE International in United States
Electric vehicle works on stored energy inside the batteries or cells. These units needs to be regulated by cool down or heat up to perform utmost. This temperature regulation also ensure individual battery or cell life. BCS are installed on vehicles to regulate the temperature around battery packs. To ensure maximum performance of these units, numerical simulation is performed and detailed optimization of flow rate as well as flow path into BCS is carried out. All the parts are assembled inside the unit as per defined packaging area or size. Numerical modelling (CFD) is performed to examine the flow path. Flow path is very important to examine, as BCS units consists of condenser. It is very important for condensers to perform efficiently, which means air flow should happen across it appropriately. If sufficient flow is not happening across the condenser, then performance of condensers comes down and optimum temperature around battery packs cannot be maintained. This will affect the performance of battery pack capacity as well as individual battery life. Based on results obtained from…
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Performance & Efficiency Improvement of Electric Vehicle Power Train

International Centre for Automotive Technology-Devesh Pareek
  • Technical Paper
  • 2019-28-2483
Published 2019-11-21 by SAE International in United States
Introduction: The advent of electric mobility is changing the conventional mobility techniques and their application in automobiles across all segments. This development comes with challenges ranging across varied sub -systems in a vehicle including Power Train, HVAC, Accessories, etc. Objective: This paper would concentrate on the Power train related sub systems & improvement of the same both in terms of Efficiency & Performance. Methodology: The electric power train consists of three major sub parts: 1. Motor Unit 2. Controller with Power electronics 3. Battery Pack with BMS We would concentrate on improving the overall efficiency and performance of all these subsystems while they perform in vehicle environment and work in tandem by deploying following techniques: a. Improved Regenerative Braking for converting vehicles Kinetic energy into electrical energy using specific algorithms and control techniques b. Optimization of Design Specs and duty cycle based on real world driving cycles. c. Innovative Heat dissipation techniques to minimize energy loss to heat. d. Efficient Electrical to Chemical Energy conversion and vice versa through use of optimization techniques based on…
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Recommended Practice for Performance Rating of Electric Vehicle Battery Modules

Battery Standards Testing Committee
  • Ground Vehicle Standard
  • J1798_201911
  • Current
Published 2019-11-13 by SAE International in United States
This SAE Recommended Practice provides for common test and verification methods to determine Electric Vehicle battery module performance. The document creates the necessary performance standards to determine (a) what the basic performance of EV battery modules is; and (b) whether battery modules meet minimum performance specification established by vehicle manufacturers or other purchasers. Specific values for these minimum performance specifications are not a part of this document.
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

New-Vehicle Collision Repair Information

Motor Vehicle Council
  • Ground Vehicle Standard
  • J2376_201910
  • Current
Published 2019-10-28 by SAE International in United States
This SAE Recommended Practice defines the various types of information required by the collision repair industry to properly restore light-duty, highway vehicles to their pre-accident condition. Procedures and specifications are defined for damage-related repairs to body, mechanical, electrical, steering, suspension, and safety systems. The distribution method and publication timeliness are also considered.
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Thermal Behavior Analysis of Lithium Ion Cells used in EVs and HEVs

A R A I-Aatmesh Jain
College of Engineering-Shubham Gaurishankar Lonkar
Published 2019-10-11 by SAE International in United States
The batteries for electric vehicles (EV) generate heat during discharging cycles. During these rapid discharge cycles the temperature of cell may increase above allowable limits. The high temperature of lithium ion cell is the primary factor affecting the cell performance and life. To develop efficient cooling mechanism for batteries, thermal behavior of secondary cell is must know. In this research, experimentally the thermal behavior analysis of cylindrical lithium ion cells at constant current discharge cycles with different current rates for each cycle is evaluated. The experiments were carried out at three discharge cycles of 1C, 2C and 3C rates and two battery chemistries namely NiMnCo and NiCoAlare considered for analysis. The instantaneous temperature of cell was measured using thermal imager and increase in overall cell surface temperature at different discharge rates, for entire discharging interval has been studied. An empirical relation for average surface temperature of cell at different current rates and depth of discharge has been obtained which may find application in defining the discharge algorithms. The rates of internal heat generation in both…
This content contains downloadable datasets
Annotation ability available