Building the
New Economy of Movement

ELECTRIC VEHICLE BATTERYSTATE OF HEALTH
BUSINESS WHITE PAPER
MOBI SOH0001/WP/2022 Version 1.3

April 2022

MOBI
DRIVES PROGRAM
April 2022
© 2022 MOBI. All rights reserved.

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END OF TERMS AND CONDITIONSMOBI is a nonprofit alliance of many of the world’s largest
vehiclemanufacturers,

startups,

governments/transit

agencies, NGOs, financial institutions, e-mobility providers,consultancies, suppliers, logistics providers, and blockchain
protocols working to create standards and build theWeb3 digital infrastructure for connected vehicles and IoT

INTRODUCTION

commerce.
MOBI is creating simple blockchain-based standards toidentify vehicles, people, businesses, and the Trusted Trip

Vehiclesin order to securely exchange and share data, and pay formobility services, with the goal of making transportation more
efficient, equitable, decentralized, and sustainable, all while
preserving the data privacy of users and providers alike. MOBI
itself is technology and ledger agnostic.

PeopleThis standard is a foundational component of the MOBI Battery
Initiative. The MOBI Battery Initiative leverages standards from
MOBI, W3C, and others; the ITN decentralized trust network;
and Citopia’s privacy-preserving track & trace capabilities topropel the creation of a comprehensive framework to improve

Businesses

sustainability and visibility in the global battery value chain.
The MOBI Battery Initiative emphasizes collaboration between
stakeholders in the mobility, energy, and blockchain/IoT
industries.
Trusted Trip
This standard is the result of continuous workshops,
discussions, and research efforts carried out by members of
the DRIVES Program. Sincere thanks are extended to those
who contributed their unique insights to this white paper.

AUTHORS•

Pramita Mitra, Ford

•
•

•
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Garrett Graham, Accenture••

Xiaoliang Zhu, Hitachi

•
•
•

•

Praveen Abbaraju, Hitachi•

Alan Gordon, Ford•

Loren Adams, Accenture•

Kumara Guru, Blockedge

•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•

Ashish Acharya, Ford

Alessandro Arciero, Henshin
Group

Daniel Bachenheimer, Accenture
Patrick Bartsch, AWS

Massimo Belluz, Henshin Group
Roger Berg, DENSO

Emmanuel Bulti, Accenture
Zac Burt, Aucnet

Elena Carrasco, USAA

Joshua Cartellone, Accenture
Mike Casey, GM

Raullen Chai, IoTex
Alex Choo, ASJade

Leonard Dorlochter, Peaq
XinXin Fan, IoTex

Aaron Fong, Honda

Sanshiro Fukao, Itochu

Eric Pilat, Cara7•

CONTRIBUTORS•••REVIEWERS
Roger Berg, DENSO

Dean Philips, AWS•

Rajat Rajbhandari, PhD, MOBI

•

•

•
•
•
•
•
•
•
•
•
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•
•
•
•
•
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Garret Graham, Accenture

Derek Pierre, Nucypher
Yoshihide Sakai, ItochuPeter Schiekofer, Reply
Mark Shih, ASJade

Raj Srinivas, Blockedge
Sudha Sriram, Ford

Suresh Sundararaj, Ford
Ryan Tabibian, CarIQLong Tran, AWS

Xiaoliang Zhu, Hitachi

MOBI TEAM

Joel Hartshorn, USAA•

Tram Vo, Director + Founder

Yoji Kawanishi, Itochu•

Rajat Rajbhandari, Working Groups Lead

Christian Koetschan, Reply•

Subrata Kundu, Hitachi•

Arjun Hassard, Nucypher•

Jonathan Koester, Peaq•

Karthik Krishnamurthy, AWS•

Chris Ballinger, Advisor + Founder
Betul Kahya, Fellow
Matt Shi, Fellow

Griffin Haskins, Fellow

Grace Pulliam, Communications Manager

Phebe Lu, ASJade
Will Maney, USAA

Domenico Mangiacapra, Henshin Group
Piyush Manocha, Accenture
Akhilesh Mishra, GM

Hiroaki Murase, Itochu

Yasuhiro Nakamaya, Aucnet
Richard Nolk, CEVT

Haruobu Ohmae, Itochu
Larry Pang, IoTex

CONTACT
info@dlt.mobi

TABLE OF
CONTENTS

01

Executive Summary

03

Glossary of terms

					
04

Objectives of this White Paper		

05

Definition of Battery State of Health07

Nuanced SOH Definitions

11

SOH Estimation Methods

13

Business Applications of SOH

17

State of Health in Regulatory Requirements•

European Union’s Proposed Battery Directive•

SOH Standardization Proposal by the
California Air Resources Board

			

19

Tamper Proofing of SOH Records

20

Problem Definitions

21

Potential Solutions

22

Role of MOBI Moving Forward

24

Bibliography

MOBI SOH0001/WP/2022 Version 1.3

Tracking battery

There is little doubt about the growth of the Electric Vehicle (EV)performance, or SOH, will

market globally. One estimate puts it to reach USD 175.11 billion by

be key to unlocking circular

2028, at a CAGR of 26.0% during the forecast period of 2021-2028.

business models in the

At the same time, the global EV battery market is projected to growrapidly expanding global EV

at a CAGR of 25.3% from USD 27.3 billion in 2021 to USD 67.2 billion bymarket.

2025. The market growth of EVs and batteries have created a new
set of challenges to the industry.

EXECUTIVE SUMMARY

Although the cost of production is decreasing on a USD/kwHbasis, batteries in EVs are one of the most expensive components.
Because of the growing EV market, there is an increasing interest inunderstanding the performance (and degradation) of EV batteries,
which is tied to the overall performance of a vehicle and hence
its market value. The performance of an EV battery is represented
by its State of Health (SOH), more specifically how it changes overtime after a vehicle has been in use. There are business models
emerging in which EV batteries are repurposed for “second life”
after the batteries are deemed unsuitable for EV use becauseof SOH degradation over time. EV batteries also pose a serious
environmental and social challenge if their chemical components
are not reused and recycled, which rides upon accurate estimationand tracking of the SOH.
MOBI’s Battery SOH Standard
investigates current methods
for SOH tracking, regulatorycompliance requirements,
andthe emerging need for
an industry-wide framework
for tracking and sharing SOH
data.

MOBI’s goal through this document is to provide its stakeholders
the state of the art about the battery SOH. It is important for themembers to know how the battery SOH is defined, measured, andestimated, and also how the SOH is being used as a key parameterin various business applications and regulatory compliance. With a
lot riding on the battery SOH, secure provenance, tamper-evident
storage, and reporting of this data between the battery value
chain stakeholders will become paramount. There may be a needto create a standardized framework for how the SOH is measured,stored, reported, and provided to stakeholders in the entire battery
value chain.

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GLOSSARY OF TERMS
Battery State of Health(SOH)

Ratio of total maximum capacity (in kWh) at any given timeover beginning of life capacity (or rated capacity). The SOH
deteriorates over long periods of usage impacting the battery’s
overall performance.

Battery State of Charge(SOC)

Almost as important as the SOH, SOC is the remaining capacity/
total capacity or rated capacity. As the battery ages, remaining
capacity decreases.

Battery Management System(BMS)

A battery management system (BMS) manages a battery
pack and monitors the operating state of modules and cells,
calculates and reports various performance data, and balances
the performance of individual cells and modules.

Circular Business Model(CBM)

It pertains to extending the second life of batteries and extracting
as much monetary and environmental benefits as possible until

OBJECTIVES OF
THIS WHITE PAPER
The objectives of this white paper are fourfold:
Identify commonly used definitions of battery state of health (SOH). Determine if there
are any conflicts and deviations in the definitions.

the batteries reach the end of life. At that point, batteries arerecycled or completely disposed of.

Second Life of Batteries

Gather the state of the art in estimating battery state of health.

Rechargeable batteries after their SOH has reduced and reacheda certain level that makes it inefficient for its first intended
use, can then be used for other purposes (or second life). For
example, EV batteries can be reused for home storage after it

Outline existing and potential business applications as well as regulatory complianceinvolving EV battery performance.

has been declared unsuitable for EV use.
Identify problems that the stakeholders could face in the foreseeable future and present
potential solutions.

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DEFINITION OF BATTERY STATE OF HEALTH
Once battery SOH reaches

Across academia and industry, the definition of battery SOH was

SOH is not the only

As described in Chapter 5 of this document, there are somea ratio of 80%, the battery

found to be consistent and is calculated by a ratio of total maximum

parameter that defines

disagreements as to whether the SOH should include bothneeds to be replaced andcapacity (in kWh) at any given time over beginning of life capacity

battery performance andcapacity fade and impedance growth or just capacity fade. There

the pack repurposed for its(or rated capacity). Both sectors agree that when the ratio reaches

life. State of Charge (SOC)

are arguments about where SOH is adequate to define a battery’s

second life.

80% then the battery has reached its end of life, which means theis another key metric foroverall health. In that case, SOH is not the only parameter thatbattery needs to be replaced and the original pack repurposed for

tracking a battery’s overall

defines battery performance and life. State of Charge (SOC) is also

its “second life.” Because batteries include cells, modules, and ahealth.

important. SOC is the remaining capacity/total capacity or rated

pack, the definition of SOH carries for individual components in thecapacity. As the battery ages, remaining capacity decreases.

pack.

As shown in Figure 1, the battery SOH can be also calculated using impedance (or resistance) andrepresents the thermal limit of the battery. When the SOH is measured using capacity, it is also referred
to as “Capacity Fade” as maximum capacity decreases over time.

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NUANCED SOH DEFINITIONS

Panasonic (2019)

Li et al (2020)“SOH is the ratio between the initial charge and the amount of charge that has deteriorated over“The SOH of the battery is a metric to indicate the battery’s aging level. The commonly used SOH

time. The amount of charge is measured by the current integration method (Coulomb counting),

indices can be divided into two groups: capacity fade indices and power fade indices. With battery

etc. by a Battery Management System (BMS.) The current SOH can be calculated by storing theaging, the value of the remaining capacity of the battery will decrease because of the capacity

charge amount at the start of use and comparing it with the current charge amount. However,loss mechanisms, resulting in the capacity fade of the Battery. In this work, the SOH indicating

SOH has no direct correlation with various lithium-ion battery deterioration phenomena such as

the battery’s capacity fade, SOHC, and the SOH indicating the battery’s power fade, SOHR, areelectrode deterioration due to metal lithium deposition (dendrites) and electrolyte deterioration.

determined synchronously.

Therefore, the SOH measurement is for obtaining the current charge amount, it cannot estimate
the future SOH, and is different from the deterioration diagnosis.”

The SOHC of the battery is usually defined as follows = CN,t / CN,0
where CN,0 and CN,t are the nominal capacity and the remaining capacity at current time t.

Texas Instruments (2019)“Previously, the SOH of a battery was typically represented by the actual runtime
FullChargeCapacity/Design Capacity (or FCC/DC). Using the runtime FCC, however,
was not a very good representation for the state-of-health because the runtime FCC
reflects the usable capacity under load. A high current load reduces the runtime FCC.
If using just the FCC/DC calculation for SOH, the SOH under high load will be worse thanthe SOH under typical load. However, a smaller usable capacity at high load does notmean the SOH of a battery is degraded. This is the same when FCC is reduced at a

The SOHR of the battery is determined = R0,t / R0,0
where R0,0 and R0,t are the ohmic resistance at battery’s begin of life
(BoL) and current time t.
The End of Life (EOL) of the battery regarding the capacity fade is reached when the value of
SOHC,t as shown in (29), equals 80%. However, the EOL can also be defined as the time that thevalue of the ohmic resistance increases 30%, i.e. the value of SOHR,t reaches 130%, considering thebattery’s power fade, as shown in (30). Therefore, it is essential to estimate both SOHC,t and SOHR,tat the same time.”

lower temperature. The SOH is calculated using the FCC simulated at 25C with current
specified by SOH Load Rate. The SOH Load Rate can be set to the typical current of theapplication, and it is specified in hour-rate (that is, Design Capacity/SOH Load Rate will

Lina et al (2015)

be the current used for the SOH simulation).”“In order to evaluate the aging level of lithium-ion batteries, several indicators or notions are
created. The state of health is the most-used indicator in the literature. Meanwhile, the relative
capacity which interprets SOH and capacity loss of batteries. The cell relative capacity could be
calculated by the following equation.
Crelative = Cnp/Cn0

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NUANCED SOH DEFINITIONS
where Cnp represents the capacity of current cells, Cn0 represents the initial capacity of a cell
before the cycle test, and Crelative represents the relative capacity of current cells. Generally, thebattery is considered to reach its end of life when the battery capacity fades to 80% of its initialvalue. This indicator represents the battery fades.”Murnane and Ghazel“A fully charged battery has the maximal releasable capacity (Cmax), which can be different
from the rated capacity. In general, Cmax is to some extent different from Crated for a newly usedbattery and will decline with the used time. It can be used for evaluating the SOH of a battery.

Li et al (2020)

SOH =Cmax/Created”“SOH is calculated by the common judgment method of current research capacity, thatis, the ratio of the maximum amount of electricity released by the battery in the use of
the vehicle to the factory capacity marked on the nameplate of the vehicle battery, as
shown in SOH = Qaged/ Qnew”

Singh et al (2019)“Theoretically, the SoH of a fresh battery is 100% and will decrease over time due to its usage. SOH
is an indicator to describe the health status of a battery, and it can reflect the performance andBak et al (2019)“In order to manage the battery efficiently, it is necessary to accurately estimate andaging of the battery. In terms of electrical quantity, SOH is an indicator of the remaining full battery
capacity. SOH is generally defined as the ratio of the maximum releasable capacity of a battery to
the rated capacity of the battery when it is fresh.”manage the battery SOH and Remaining Useful life (RUL). SOH represents the maximum
discharge capacity to the rated capacity of batteries. Since the maximum discharge
capacity is characteristic of battery aging, SOH is used as an indicator of degree of
aging. SOH of the new battery with no degradation is processed in 100%. When SOH value
reaches 80%, that is the time for the replacement and can be regarded as reaching an
EOL. RUL represents the remaining life until the EOL.”

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SOH ESTIMATION METHODS
Estimating SOH is complicated as many factors from the ambient environment or from charge andModel-based methods

Model-based methods use empirical models, curve fitting,discharge cycles generate different aging effects. This makes the SOH estimation a difficult task, andare more feasible for real-

statistical linear and non-linear models, differential equations,throughout the years, many studies have tried to explore the aging mechanisms.

time deployment but canmachine learning, neural networks, etc., to estimate SOH or

be rendered useless bycapacity degradation over time and into the future. Due to theirunexpected changes in thereal time feasibility, model-based methods for estimating SOH

operating conditions.

have gathered significant interest in the industry. Model-based

According to Noura et al (2020) there are two broad categories of SOH estimation methods for
EV Lithium Ion batteries. Those categories are following:•

methods can be deployed in the BMS. However, any deviation fromthe training data because of new operating conditions can render

Experimental methods - direct measurement of impedance, internal resistance,

the estimation useless.

capacity levels using laboratory devices such as spectroscopy.

•

Model-based methods - based on physical equations and curve fitting, machinelearning algorithms.

Despite being highly

Experimental methods are typically conducted in laboratories

accurate, experimental

with specific equipment and are often time consuming (several

methods for measuring

hours). It is worthwhile to note that several companies (including

battery SOH are costly, time-

MOBI members) are working on quicker battery SoH diagnostics,

consuming, and not capable

and technical breakthroughs are expected to enable integration ofof measuring degradation

experimental and model-based methods into diagnostics systems

over time.

through data coordination with the battery management system in

The key issue is finding the

A combination of experimental and model-based methods has

ideal compromise between

also been proposed. In this method, data gathered from theexperimental and model-

experimental methods are used as training data sets and fed into

based methods to ensuremodel-based methods. The availability of such data is beneficial

accuracy, cost efficiency,

to methods that use neural networks that by nature require large

and real-time reporting

data sets.

capabilities.
Obtaining a complete battery SOH diagnosis considering every
aging factor and compatibility with an EV application remains
a major challenge. Currently, the key issue for aging estimation
is finding the ideal compromise between various methods
considering their application in EVs.

vehicles. These methods measure battery internal resistance andimpedance using techniques such as Electrochemical ImpedanceSpectroscopy and measure battery internal resistance behavior indifferent working conditions with a very satisfying accuracy. Thesemethods are costly but accurate. Because experimental methods
provide a snapshot of battery performance at a given time or shortperiod of time, they cannot measure the battery’s degradation
over time and over several cycles. Obviously, they are not suitable
to be included in the battery management system in vehicles.

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BUSINESS APPLICATIONS OF SOH
Battery SOH data will be a

As rechargeable batteries become more and more ubiquitous,

powerful tool for stakeholders

discussions about their performance (as well as methods ofacross the value chain toestimation) will become more prominent. End consumers will wantunlock more transparent andto know initial SOH and how it will degrade over time for the vehiclesustainable business models.

of their choice before making purchasing decisions. Insurancecompanies may want to know the residual value of batteries tocorrectly underwrite them. Lenders would want to know whether toInsurance Companies:
Insurers will be able toInsurance

leverage battery SOH data

battery performance to estimate the battery replacement costs

for underwriting purposes.

or underwrite battery warranties. Insurance giant Munich Re

companiesmay

requirecorrect

assessmentof

recently announced that it will offer a product that covers battery

extend the warranty of the vehicle or not.

performance (Munich Re, 2019). Their product allows manufacturers
in the battery market to offer long-term performance guarantees
whose value is backed by the insurance coverage. According to

The following section outlines use cases/applications of battery SOH from the perspectives of various

their website, “The new coverage allows battery manufacturers

stakeholders:

to insure their customer warranties. For example, if the repair or
replacement costs of defective or weak battery modules exceed

End Users (Vehicle Owners and Fleet Owners):

a predetermined amount, the insurance then covers the rest.
Manufacturers can thus unburden their balance sheets.”

Vehicle owners can use SOH

The SOH is used in determining the current maximum range of EVs.

data to determine when to

Current maximum range of an EV = current SOH x rated beginning

replace a battery and assessof life range = 90% x 300 km = 270 km.

their EV’s value based onremaining capacity.

Vehicle owners can use this information to determine timeremaining before the battery has to be replaced and compare
their EV’s value based on remaining capacity.

OEMs and Battery Suppliers:
Battery performance,

Because batteries are a critical component of EVs, an EV’s range —especially the SOH, will beand, by extension, its value — will be tied to the battery’s performance.

a key parameter that will

Battery performance, especially the SOH, will be a key parameter

influence consumers’ vehicle

that will influence consumers’ vehicle buying choices. OEMs arebuying choices.

also responsible for battery recalls, maintenance services, andmanagement of battery warranties. Both OEMs and suppliers will
have a responsibility to comply with future regulations regarding
standardized reporting of SOH as well as battery recycling/
repurposing.

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BUSINESS APPLICATIONS OF SOH

Battery Passport:

Circular Business Models:Battery SOH is one of theBattery Passport is a tool being developed by the Global Battery

Circular business models

key attributes the battery

Circular Business Models (CBMs) pertain to extending theAlliance and other vendors such as EverLedger to track the life

assume that second life or

passport will track and makesecond life of batteries and extracting as much monetary andcycle of batteries, including second life. Battery SOH is one of

repurposing will increaseavailable to stakeholders inenvironmental benefits as possible until the end of life (Olson et.

the key attributes the passport will track and make available tobusiness opportunities forthe value chain.

al., 2018). For example, EV Batteries with < 80% SOH can still be usedstakeholders in the battery value chain.

stakeholders and reduce thefor other purposes such as home energy storage (Clement et. al.,burden on recycling, which2020). There is no clear consensus at which point the OEMs send

can be quite expensive.

the modules to recyclers and for how long recyclers continue to
use the modules for different uses such as home energy.
These models assume that second life or repurposing will increasebusiness opportunities for stakeholders and reduce the burden on
recycling, which can be quite expensive. Hence, CBMs extend thevalue chain of batteries beyond first life.
CBMs will require close collaboration between different stakeholders
to build trust and reduce uncertainties regarding the performanceof the battery and its individual components. It appears CBMs rely
not only on being able to accurately determine the performance ofbatteries but also on how quickly these measures (e.g., SOH) canbe determined (Albertson et. al., 2021).

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STATE OF HEALTH IN REGULATORY REQUIREMENTS
in Annex VII. Access to the data on those parameters in the battery management system

European Union’s Proposed Battery Directive

shall be provided to the legal or natural person who has legally purchased the battery

The proposed Battery

In 2020, the European Commission published a proposal for

Directive builds on

Regulation of the European Parliament and of the Council concerning

commitments and reports

batteries and waste batteries (EU, 2020).

adopted by the European

modernize the EU’s legislative framework for batteries. It builds on

Commission, including thecommitments and reports adopted by the European Commission,

strategic action plan on

including the strategic action plan on batteries, the new circularbatteries, the new circular

economy action plan, the new industrial strategy for Europe,

economy action plan, theand the sustainable and smart mobility strategy, which aims at

new industrial strategy fordelivering a 90% reduction in transport-related GHG emissions by

Europe, and the sustainable

2050. The proposal’s objectives are threefold: 1) strengthening theand smart mobility strategy.

functioning of the internal market (including products, processes,

This proposal aims toor any third party acting on their behalf at any time for evaluating the residual value ofthe battery, facilitating the reuse, repurposing or remanufacturing of the battery and formaking the battery available to independent aggregators operating virtual power plants inelectricity grids.
Article 59 requires that in order to document that a battery is no longer waste, the operator carryingout the relevant operation shall demonstrate the following upon request by a competent authority
amongst other parameters the evidence of state of health evaluation or testing and that thisinformation shall be made available to end users and third parties acting on their behalf, on equalterms and conditions, as part of the technical documentation accompanying the repurposed battery
when placed on the market or put into service.

waste batteries, and recyclates), by ensuring a level playing field
through a common set of rules; 2) promoting a circular economy;
and 3) reducing environmental and social impacts throughout allstages of the battery life cycle.
The proposal considers second life of batteries (repurposing),
collection targets, recycling and recovery of materials, carbon
footprint declarations, and information management of battery
performance throughout the lifecycle.
The proposal specifies that the end of life criteria of batteries
include a state of health check before being sent to repurposing
or recycling.
Article 14 of the proposal requires that
…rechargeable industrial batteries and electric vehicle batteries shall contain a battery
management system that stores the information and data needed to determine the stateof health and expected lifetime of batteries in accordance with the parameters laid down17

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SOH Standardization Proposal by the California Air Resources Board
Draft regulations from theIn December of 2021, the California Air Resources Board (CARB)

California Air Resources

presented draft regulations establishing a zero-emission in-use

Board (CARB) establish

verification report to be submitted by the vehicle manufacturers toa standardize set of

CARB (CARB, 2021). These regulations establish enforcement testingprocedures for vehicle

procedures to be used by CARB to periodically evaluate vehicles

manufacturers related tofor compliance in addition to procedures and requirements for

SOH tracking and reporting.

remedial actions.
The regulation will require OEMs to calculate battery’s SOH suchthat it is:•

Readable by drivers without a tool.

•

Normalized (100% equals new on all cars).

The regulation will also require OEMs to define and disclose SOH
value that qualifies for warranty repair.

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TAMPER PROOFING OF SOH RECORDS

For use cases such as

For use cases such as Battery Passport and others mentioned inBattery Passport and others

previous sections, it is clear that the industry will require tools by

mentioned in previous

which the battery’s SOH values are tamper-proof and tamper-

sections, it is clear that theevident. Such a requirement will allow the stakeholders to trust theindustry will require tools

validity of the SOH data with a high confidence. The SOH values

by which the battery’s SOH

measured by the maintenance service providers and by the BMS

values are tamper-proof andmust be tamper-proof. The need for such a requirement is thetamper-evident.

same as and even greater than tamper-proofing the odometerreading in vehicles.
Blockchain technology has been proposed by Ding, Gowda et. al.,and Florea et. al., to create a framework to secure SOH values of EV
batteries.
Ding (2018) proposed creating a hash of battery test reports and

PROBLEM DEFINITIONS

Following is a list of problems identified in the earlier chapters.

Lack of industry-wide standards to define and present battery SOH to end users andother value chain stakeholders for various use cases (i.e., recollection, repurposing, andrecycling) including comparing performance of new and used batteries.
Lack of clarity in value chain mapping of stakeholders that require SOH information.
Lack of industry-wide requirements/framework to create tamper-proof/tamperevident battery SOH records, which covers the following - verification system is needed
for trust among vehicle OEMs and battery manufacturers to be incentivized for recycling
programs to either share SOH values or the parameters necessary for third parties tocalculate and monitor battery performance for the purposes described in the problems
above.

storing the transaction in a consortium blockchain. That way otherstakeholders in the value chain can share and verify the correctnessof the test reports and values with regard to the SOH. Gowda et.
al. (2021) proposed a similar concept of storing battery SOH data
and the cost of degradation in a consortium blockchain for theelectric vehicle grid integration use case. Florea (2020) proposed a
blockchain application for the electric vehicle battery charge andswap use case. The battery voltage and state of charge (SOC) is
continuously monitored and the data is stored on the blockchain
together with the required functionalities such as user and battery
information and charge/swap requests.

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MOBI SOH0001/WP/2022 Version 1.3

POTENTIAL SOLUTIONSMOBI SOH0001/WP/2022 Version 1.3

ROLE OF MOBI MOVING FORWARD

MOBI is working on

MOBI ecosystem includes a diverse set of battery value chain

decentralized battery

stakeholders. From the literature view above, it is clear that theidentities and building theecosystem requires open standards, frameworks, and reference

Create an industry standard definition of SOH. Develop a guideline for how SOH information should

Web3 infrastructure for

implementations to define, gather, share, and present tamper-

be consumed by the stakeholders for various use cases.

secure, trusted data sharing.

evident battery SOH related information and history, especially in

Solution(s) for Problem 1

second life use cases. MOBI is working on decentralized battery
identities based on W3C standards and building the Web3

Solution(s) for Problem 2

infrastructure:•

infrastructure to provide trusted identity services.

Comprehensive value chain mapping of stakeholders and various business applications that
require SOH. The mapping should include provenance of SOH information between stakeholders
for the use cases discussed previously. Following the mapping, a detailed analysis of the EV
battery value chain will be helpful for the industry to understand the potential bottlenecks, risks,and opportunities for SOH reporting and consumption.

The Integrated Trust Network (ITN) is a protocol-agnostic digital•

Citopia is a decentralized marketplace to onboard SelfSovereign Digital Twins and enable Verifiable Credentials
issuance for business automation using Zero-Knowledge (ZK)
Proofs. Citopia enables countless track and trace use casesin the supply chain and unlocks marginal cost pricing for

Solution(s) for Problem 3

numerous mobility-as-a-service transactions.

It is imperative from the literature review that the SOH information will be valuable data upon which
many business applications will rely. The same way there are many applications and processes inplace to ensure tamper proofing of odometer readings, the industry should develop frameworks
to ensure the SOH information is tamper-proof and tamper-evident.

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Stakeholders can use

Battery and EV stakeholders can use MOBI standards and the Web3

MOBI’s Web3 infrastructure

infrastructure to create traceable and tamper-evident multi-

to enhance trusted data

party applications to share the SOH related information with othersharing and interoperability

stakeholders in the battery value chain. These applications couldin the battery supply chain.

include:•Information about the battery manufacture for purposesof monitoring sourcing, sustainability, carbon footprint, and•“Advanced Clean Cars (ACC) II Workshop.” CARB, May 6, 2021. https://ww2.arb.ca.gov/sites/default/
files/2021-05/acc2_workshop_slides_may062021_ac.pdf

supply chain efficiency, etc.

Albertsen, Levke, Jessika Luth Richter, Philip Peck, Carl Dalhammar, and Andrius Plepys. “Circular

Information about the battery use and health for purposes

Manufacturers and Policies in the EU.” Resources, Conservation and Recycling 172 (September 2021):

ofestablishingvalue,

battery

Business Models for Electric Vehicle Lithium-Ion Batteries: An Analysis of Current Practices of Vehicle
swapping,

suitability

fordecentralized green energy storage, etc.
•

BIBLIOGRAPHY

Information about second and third uses and ultimately
disposal.

105658. https://doi.org/10.1016/j.resconrec.2021.105658.
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