Post on 31-Jul-2020
Damien Frost and David Howey
Department of Engineering Science, University of Oxford
http://users.ox.ac.uk/~engs1053/
WIFI ENABLED BATTERY MANAGEMENT
SYSTEMS: USING THE INTERNET OF THINGS
TO ENHANCE BATTERY TECHNOLOGY
UKES 2016
2nd December 2016
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1 Wifi Enabled Battery Management Systems: Using the Internet of Things to
Enhance Battery Technology
Introduction and Motivation
Industry Examples
Our Solution
Current Projects
Security
Battery Degradation
Internet Connected Battery
Battery Degradation
D. Frost & D. Howey
• “Batteries suck.” – Elon Musk
• Want to know when they will fail
• Battery modelling can help
2
Battery Degradation
Wifi Enabled Battery Management Systems: Using the Internet of Things to
Enhance Battery Technology D. Frost & D. Howey
Introduction and Motivation
Industry Examples
Our Solution
Current Projects
Security
Battery Degradation
Internet Connected Battery
3
Internet Connected Battery
• Getting more data can help build
more accurate models
• Acquiring data is difficult, and time
consuming
Image credit: binasmartbusiness.com
Wifi Enabled Battery Management Systems: Using the Internet of Things to
Enhance Battery Technology D. Frost & D. Howey
Introduction and Motivation
Industry Examples
Our Solution
Current Projects
Security
Battery Degradation
Internet Connected Battery
4
Renobat
DeWALT
Roost
Renobat
• Most of their business is from selling
a battery desulfation service for lead
acid batteries
• Starting to move monitoring to the
cloud, for preventative maintenance
Image credits: www.renobat.eu/en/
Wifi Enabled Battery Management Systems: Using the Internet of Things to
Enhance Battery Technology D. Frost & D. Howey
Introduction and Motivation
Industry Examples
Our Solution
Current Projects
Security
5
DeWALT
• Manage and track battery packs for
power tools
• Check SoC, temperature, diagnostics
from the App
• Mostly sold as a security feature
Image credits: www.dewalt.co.uk
Wifi Enabled Battery Management Systems: Using the Internet of Things to
Enhance Battery Technology D. Frost & D. Howey
Introduction and Motivation
Industry Examples
Our Solution
Current Projects
Security
Renobat
DeWALT
Roost
6
Roost
• Wifi connected Lithium ion battery in
the form factor of a 9V battery
• The battery connects to wifi, and can
send alerts to your smart phone
• Can snooze the alarm with the app
Image credits: www.getroost.com
Wifi Enabled Battery Management Systems: Using the Internet of Things to
Enhance Battery Technology D. Frost & D. Howey
Introduction and Motivation
Industry Examples
Our Solution
Current Projects
Security
Renobat
DeWALT
Roost
7
Overview
• Every solution today is bespoke
• A true IoT device could communicate
with any other device on the
internet, however compromises must
be made
• Our goal: create an open battery
repository and hardware
Hello Mr.
Battery!
Who are
you???
Wifi Enabled Battery Management Systems: Using the Internet of Things to
Enhance Battery Technology D. Frost & D. Howey
Introduction and Motivation
Industry Examples
Our Solution
Current Projects
Security
Overview
Physical Layer
Communication Protocol
Hardware
Complete System
8
Overview
Physical Layer
Communication Protocol
Hardware
Complete System
Overview
• Collecting battery data has many
benefits
• Greater user interaction and learning
• More complex models could be
verified
Wifi Enabled Battery Management Systems: Using the Internet of Things to
Enhance Battery Technology D. Frost & D. Howey
Preventative
Maintenance
Introduction and Motivation
Industry Examples
Our Solution
Current Projects
Security
9
Overview
• What is the best way to bridge the
gap between the device and the
internet?
• Low cost microcontrollers do not
have the same high level protocols as
servers
?
Low Level
Interfaces
High Level
Interfaces
Wifi Enabled Battery Management Systems: Using the Internet of Things to
Enhance Battery Technology D. Frost & D. Howey
Introduction and Motivation
Industry Examples
Our Solution
Current Projects
Security
Overview
Physical Layer
Communication Protocol
Hardware
Complete System
10
Physical Layer
• Wi-Fi is ubiquitous
• Decently scalable
• Easily interface with servers and PCs
• Passive Wi-Fi consumes 10,000x less
power than conventional chipsets [1]
Wifi Enabled Battery Management Systems: Using the Internet of Things to
Enhance Battery Technology D. Frost & D. Howey
Introduction and Motivation
Industry Examples
Our Solution
Current Projects
Security
Overview
Physical Layer
Communication Protocol
Hardware
Complete System
[1] B. Kellogg, V. Talla, S. Gollakota, and J. R. Smith, “Passive Wi-Fi: Bringing Low Power to Wi-Fi Transmissions,” USENIX Symp. Networked Syst. Des. Implement., 2016.
11
Communication Protocol
• The communication protocol is like
the language of the system
• There are as many as 7 different
protocols suitable for IoT devices
• We have decided to use WebSockets
Hello!
Bonjour!
???
Wifi Enabled Battery Management Systems: Using the Internet of Things to
Enhance Battery Technology D. Frost & D. Howey
Introduction and Motivation
Industry Examples
Our Solution
Current Projects
Security
Overview
Physical Layer
Communication Protocol
Hardware
Complete System
12
Hardware
• MCU: STM32F401RET6
• 512 kB Flash • 84 MHz CPU Frequency • 12 bit ADC
• Wi-Fi Module: RN171
• 802.11 b/g • 54 Mbps
Wifi Enabled Battery Management Systems: Using the Internet of Things to
Enhance Battery Technology D. Frost & D. Howey
Introduction and Motivation
Industry Examples
Our Solution
Current Projects
Security
Overview
Physical Layer
Communication Protocol
Hardware
Complete System
13
Complete System
IoT Device
Wi-Fi Shield
NUCLEO-F401RE
Serial 1 TX
Serial 1 RX
D5(TCP Status)
D6(Wifi Reset)
RN-171 Module
Main Program
PC
WebSocket Server
Python Server
Tornado Web Server
Router
UART
WiFly Interface
WebSocket Client
Wifi Enabled Battery Management Systems: Using the Internet of Things to
Enhance Battery Technology D. Frost & D. Howey
Introduction and Motivation
Industry Examples
Our Solution
Current Projects
Security
Overview
Physical Layer
Communication Protocol
Hardware
Complete System
http://epg.eng.ox.ac.uk/content/creating-your-own-iot-network-iot-part-1-3
14
Complete System
Wifi Enabled Battery Management Systems: Using the Internet of Things to
Enhance Battery Technology D. Frost & D. Howey
Introduction and Motivation
Industry Examples
Our Solution
Current Projects
Security
Overview
Physical Layer
Communication Protocol
Hardware
Complete System
http://epg.eng.ox.ac.uk/content/creating-your-own-iot-network-iot-part-1-3
15
Connected Smart Cell
Connected Modular Battery Pack
Connected Smart Cell
• Each cell implements a decentralized
control algorithm to synchronize its
switching actions [3]
• Wi-Fi is used for debugging and
monitoring of the cells
• A WebSocket server runs on a PC and
collects data as the system is running
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Wifi Enabled Battery Management Systems: Using the Internet of Things to
Enhance Battery Technology D. Frost & D. Howey
Introduction and Motivation
Industry Examples
Our Solution
Current Projects
Security
[3] D. F. Frost and D. A. Howey, “Novel MMC control for active balancing and minimum ripple current in series-connected battery
strings,” 2015 17th Eur. Conf. Power Electron. Appl. (EPE’15 ECCE-Europe), pp. 1–10, 2015.
16
Connected Modular Battery Pack
• Modular battery pack designed for
re-purposed lithium ion cells
• 24 modules connected to a master
which has a Wi-Fi connection
• Module-level monitoring and control
Wifi Enabled Battery Management Systems: Using the Internet of Things to
Enhance Battery Technology D. Frost & D. Howey
Introduction and Motivation
Industry Examples
Our Solution
Current Projects
Security
Connected Smart Cell
Connected Modular Battery Pack
17
Security and Privacy
Security and Privacy
• Hacking
• New protocols to distinguish real data
requests [2]
• Weigh the Pros and Cons
[2] C. Gehrmann, M. Tiloca, and R. Hoglund, “SMACK: Short message authentication check against battery exhaustion in the Internet of
Things,” 2015 12th Annu. IEEE Int. Conf. Sensing, Commun. Networking, SECON 2015, pp. 274–282, 2015.
bbc.co.uk
fortune.com
nbcnews.com
Wifi Enabled Battery Management Systems: Using the Internet of Things to
Enhance Battery Technology D. Frost & D. Howey
Introduction and Motivation
Industry Examples
Our Solution
Current Projects
Security
18
Conclusions
• Big data is playing a role in battery
technology
• Big data can help us build better
battery models, which will in turn help
us predict the lifespan of a cell or pack
• Software and hardware are needed to
realize the data needs
• An IoT ‘starter kit’ was developed
• Future work will be focused on
creating a battery data bank
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Wifi Enabled Battery Management Systems: Using the Internet of Things to
Enhance Battery Technology D. Frost & D. Howey
Introduction and Motivation
Industry Examples
Our Solution
Current Projects
Security
19
Questions?
Thank You
Contact Information:
Damien Frost
damien.frost@eng.ox.ac.uk
IoT Tutorial:
http://epg.eng.ox.ac.uk/content/creating-your-own-iot-network-iot-part-1-3
EPG Group Website
epg.eng.ox.ac.uk
Howey Research Group Website
users.ox.ac.uk/~engs1053
Introduction and Motivation
Industry Examples
Our Solution
Current Projects
Security
Wifi Enabled Battery Management Systems: Using the Internet of Things to
Enhance Battery Technology D. Frost & D. Howey