Li-ion Batteries: Benefits & Risks,

Regulation & Management

Dr Alex Martin

C&R Webinar, 28 February 2018

Agenda

• Brief introduction to the technology.

• The benefits provided by Li-ion batteries.

• Risks posed.

• EU regulatory context: product safety and environmental considerations.

• Transportation.

• Testing.

• Supplier evaluation.

RINA Overview

• Originally established in 1861, RINA is an Italian-owned business active across

testing, inspection and certification as well as in engineering consultancy.

• In recent years it has grown through acquisitions, including Edif ERA (ERA

Technology Ltd) in 2016.

• As of 2018, RINA has a global network of 3,700 professionals across 65

countries.

• At Leatherhead in the UK, RINA’s Industry service spans forensic engineering

and consultancy on technical and environmental regulation affecting electrical

and electronic equipment.

Product Regulatory Compliance

Support with product-related requirements, including:

Circular Economy

Global

Market Access

Chemicals

Responsible

Sourcing

The Technology, Benefits &

Risks

Technology & Terminology - 1

• Batteries are the components sold to users and can consist of one or more

cells.

• A cell is an individual electrochemical module with an anode and a cathode

separated by an electrolyte.

• Anodes are +

• Cathodes are -

Technology & Terminology - 2

• Lithium batteries are of two broad types:

• Lithium metal batteries are generally non-rechargeable and contain

metallic lithium.

• Lithium-ion (Li-ion) batteries do not contain metallic lithium and are

rechargeable.

The separator layer extends

above and below the electrodes

to maintain electrical isolation

between the electrodes.

The cathode spiral is attached

to a central cathode pin (+).

The anode spiral is attached to

the outer case (-) cathode.

A Typical Design

The Separator

• The separator plays a very important role in safety overall.

• The separator must ensure that the two electrodes are electrically isolated and

do not allow any direct current flow to occur but at the same time must allow the

easy transfer of lithium ions.

• Most modern separators are made of polyethylene or polyethylene treated

fibers. If a short circuit occurs, this causes a high temperature that melts this

layer, effectively cutting the flow of ions.

Key Benefits

High Energy Density

Battery Type Energy Wh/Kg

Lead Acid 25-50

Nickel Cadmium 50-80

Nickel Metal Hydride 50-100

Lithium-ion 125-200

[Petrol 12,000]

But…

What are the Risks?

• Some risks are inherent to the cell while other risks derive from when the cell is

integrated into a battery pack.

• The cell is the source of greatest risk.

• This is because, outside the cell, there is more scope to prevent potential safety

issues through protection circuitry or other passive protective devices (fuses,

etc.).

Risks by Cell and Battery Pack*

Cells Battery Pack

External short circuit External short circuit

Overcharge Overcharge

Mechanical robustness Mechanical robustness

Separator stability Improper component

specifications

Electrode alignment and

balance

Out-of-balance concerns

*Credit to John Copeland’s 2017 “UN Lithium Battery Testing” article in In Compliance.

1. Mechanical damage Crushing, drop damage, case penetration

2. External short circuit Faulty assembly, foreign matter between

connections, water immersion

3. Cell overcharge Defective or incorrect charging unit

4. Cell over-discharge Leakage current defect

5. Low temperature recharging Poor environmental control

6. High temperature storage Heat source, solar radiation

7. Internal short circuit Particles within separator, manufacture defect

Main Causes of Li-ion Battery

Failures

Regulation & Management

EU Safety Requirements

• Products imported or manufactured for use in the EU must be safe for their

intended purpose.

• Relevant safety requirements are found in either general or product-specific

legislation (e.g. Low Voltage, Machinery and Radio Equipment Directives). The

Batteries Directive does not, however, specify safety requirements.

• Where relevant, EU harmonised standards can be used to demonstrate

compliance. Consideration should also be given to:

• Official guidance / sector safety codes;

• State of the art, i.e. no less safe than the best available.

• Additional requirements include risk assessment/taking mitigation measures

plus the provision of suitable warnings and user instructions.

A Look at a Standard: EN 62133-2

• While it is not a harmonised standard, it is the European version of IEC 62133-

2.

• It specifies various safety requirements for portable sealed secondary cells.

Adhering to the standard means subjecting a sample battery to various tests.

These span:

• Continuous charging at constant voltage; over-charging;

• External short circuit;

• Drop;

• Thermal abuse;

• Crush;

• Transport (in this case using IEC 62281);

• Forced discharge, etc.

EU Environmental Requirements

• The EU Batteries Directive specifies substance restrictions as well as capacity

marking, battery removal, labelling and end-of-life obligations.

• Cd and Pb are restricted.

• Substances may also be restricted/subject to a disclosure requirement under

the EU REACH Regulation.

• Current REACH SVHCs are unlikely to be found in Li-ion batteries.

• But NMP or DMF as the electrolyte? DEHP plasticiser in PVC labels?

• The EU PoPs Regulation bans Short Chain Chlorinated Paraffins and flame

retardants that are added to PVC and rubber.

Transportation Requirements

• The transport of dangerous goods, including Li-ion batteries, is a subject of

international governance with legislation then implemented at EU/national level.

• Different bodies define obligations depending on the mode of transport:

• IATA for air.

• ADR for road.

• IMDG for shipping.

• RID for rail.

• Obligations can include:

• Requirements to use particular types of packaging/affix labels on the

outer packaging.

• Provision of correctly prepared accompanying documentation.

• Restrictions on what can be transported by weight or else the numbers

of batteries/cells.

A Look at Air and Road

• For all modes of transport, all batteries must comply with the UN Manual of

Tests and Criteria Part III.

• For air transport, IATA Packing Instructions 965-970 are notable. These specify

requirements for Li-ion batteries in equipment and as standalone items.

• Fewer obligations for <20Wh cells.

• Additional restrictions for separately shipped batteries.

• For road transport, several ADR packing instructions are notable. These are:

• P903 for new Li-ion batteries.

• P908 for damaged or defective batteries.

• P909 for used batteries returned for recycling.

Testing against UN Criteria - 1

• Testing against Section 38.3 of the UN Manual of Tests and Criteria is required

to transport Li-ion cells or batteries by all common commercial modes (e.g. air,

haulage) in almost every global locale.

• It requires testing at the cell level, battery pack level, and battery pack assembly

level.

• Commercially available cells are generally tested by cell manufacturers.

• Battery packs may be tested by the pack assembler or independently tested by

the end-device manufacturer (e.g. mobile phone manufacturer).

• It is a matter of self-certification meaning that third party testing, while common,

is optional.

Testing against UN Criteria - 2

The UN test regime is sometimes known as T1-T8 testing and covers eight key

variables. Various samples are required, with some cells and batteries subject to

50 charge-discharge cycles for aging and others tested fresh.

Preparation: 50X Cycling

T1 Altitude

T2 Thermal cycling

T3 Vibration

T4 Mechanical shock

T5 Short circuit

T6 Impact/crush (cells only)

T7 Overcharge (packs only)

T8 Forced discharge (cells only)

Cells and packs

Benefits of Testing (from Copeland, 2017)

• At the cell and pack level, the combination of cycling with short circuit at

elevated temperature may reveal internal cell problems.

• The sequence of thermal cycling, vibration and mechanical shock at both the

cell and pack level represent a severe assessment of mechanical robustness.

• Crush/impact testing also provides an assessment of mechanical robustness –

in this case to compression forces that may pose some level of internal shorting.

• Forced-discharge testing drives the cell into full voltage reversal as might

happen in an extreme out-of-balance situation.

• For packs, the T7 overcharge test simulates charging on a defective charger for

24 hours followed by 7 days in the shipping channel.

Risks by Cell and Battery Pack*

Cells Battery Pack

External short circuit External short circuit

Overcharge Overcharge

Mechanical robustness Mechanical robustness

Separator stability Improper component

specifications

Electrode alignment and

balance

Out-of-balance concerns

Green = assessed under the UN test regime

*Credit to John Copeland’s 2017 “UN Lithium Battery Testing” article in In Compliance.

Look to Other Standards

• IEC/EN 62133-2, Secondary cells and batteries containing alkaline or other non-

acid electrolytes - Safety requirements for portable sealed secondary lithium

cells, and for batteries made from them, for use in portable applications - Part 2:

Lithium systems.

• UL 1642, Standard for lithium batteries.

• UL 2054, Standard for household and commercial batteries.

Know the Manufacturing Process

• The battery manufacturing process contains many steps that can affect the

safety and reliability of a battery and the equipment it is used in:

• Consider the quality (and quality control) of the starting materials: cobalt

lithium oxide, graphitic carbon, binders, electrolytes and separators.

• The control of the thickness of the coating process.

• The avoidance of burrs and fraying at edges of cut materials that could

lead to particulate contamination on the surface of the layer.

• Attachment of electrodes and stacking of layers.

• The control of humidity levels during the final assembly and at all stages

of the assembly.

Sources & Further Information

• RINA: Nick Aitken of Forensic Engineering in Leatherhead, UK. My Product

Regulatory Compliance colleague, Dr Paul Goodman.

• John Copeland of Energy Assurance LLC, particularly a recent feature article in

In Compliance.

• Battery University.

• Compliance & Risks – C2P.

• Relevant bodies like IATA, ADR, RID, etc.

Electrical & Electronic Equipment

and the Environment

• ---

14-15 November 2018, Heathrow

Dr Alex Martin

Product Regulatory Compliance

+44 (0)1372 367032

alex.martin@rina.org

- Meeting the technical and regulatory

compliance challenges