Batteries used in medical applications can be similar to batteries used in other applications. Still, depending on the type of medical device, medical batteries' requirements can be much more stringent, especially if the medical device charges the battery while in use. Several design considerations must be addressed to ensure their safe use when used near or when the equipment is attached to the patient. Several regulatory requirements must be met. Testing is required to verify the safe operation of the battery and the medical device. This process can be simplified by implementing various design techniques to ensure a robust design while getting to market faster with lower risks—these methods, along with a high-level overview of the major regulatory hurdles that must be met, will be discussed. In this webinar, we review medical device battery pack requirements and certifications including how requirements are different from stand-alone batteries as well as what is needed for certain medical products. For more information on our custom battery pack solutions, visit https://www.epectec.com/batteries/

1. Manufacturing That Eliminates Risk & Improves Reliability
Battery Packs For Medical Devices
Requirements And Certification
2.24.21

2. Manufacturing That Eliminates Risk & Improves Reliability
2
Agenda
 Primary differences between medical batteries and standard off-the-
shelf batteries.
 Safety regulatory requirements.
 Design features required to meet these regulatory requirements.
 Going beyond just meeting regulatory, designing in features to
mitigate patient risk.
 Transportation requirements.

3. Manufacturing That Eliminates Risk & Improves Reliability
3
Primary Differences Between Medical Batteries and
Standard Off-the-Shelf Batteries

4. Manufacturing That Eliminates Risk & Improves Reliability
4
Differences In Medical Batteries And Standard Off-the-shelf
 Off-the-shelf batteries, no change control = unwanted surprises
 Medical batteries focus on safety, performance, and reliability
– More robust cell protections
– Higher quality components used
 Medical batteries may need be designed for use in electromagnetic
environment as described in IEC 60601-1-2 medical electrical
equipment
 Autoclave cleaning
 Authenticity to avoid counterfeit batteries, SHA-1/HMAC-based
 Serialized and traceable

5. Manufacturing That Eliminates Risk & Improves Reliability
5
Safety Regulatory Requirement Highlights

6. Manufacturing That Eliminates Risk & Improves Reliability
6
FDA Battery Requirements CSA group
 The FDA has recognized the following standards which products need to comply with:
– IEC 62133 Secondary cells and batteries Safety requirements for portable sealed secondary cells, and for batteries made
from them, for use in portable applications
– UL 1642 lithium cells
– UL 2054 household and commercial batteries
– IEC 60086-4 Primary batteries – Part 4: Safety of lithium batteries
– IEC 60086-5 Primary batteries – Part 5: Safety of batteries with aqueous electrolyte
– IEC 62485-X, Safety Requirements for Secondary Batteries and Battery Installations
 In addition to battery specific standards, there are standards that include battery requirements in the dental,
ophthalmic, and physical medicine fields. These currently include, but are not limited to:
– ISO 20127, Dentistry – Powered Toothbrushes – General Requirements and Test Methods
– ISO 15004-1, Ophthalmic Instruments – Fundamental Requirements and Test Methods – Part 1: General Requirements
Applicable to all Ophthalmic Instruments
– ISO 7176-25, Wheelchairs – Part 25: Batteries and Chargers for Powered Wheelchairs.
CSA Group

7. Manufacturing That Eliminates Risk & Improves Reliability
7
UN38.3 is Required Before Safety UL/IEC Testing
 Before UL2054 or IEC62133 testing can start. The battery needs to pass UN38.3
 UN38.3 Testing
– The first five tests needing to be performed in sequential order using the same
samples:
• T1. Altitude simulation,
– Simulate air transport under low-pressure conditions
– Eight (8) fully charged batteries, store at 11.6 kPa or less for at least six hours at 20C
– P/F = No mass loss beyond allowable limits, no leakage, no venting, no disassembly, no rupture, no fire and the open
circuit voltage of each battery after testing is not less than 90% of its voltage immediately prior to the test procedure.
• T2. Thermal test
– Simulates the rapid and extreme temperature changes during transport. 10 cycles of oscillating temperatures
– Eight (8) fully charged batteries, stored for at least six hours at a test temperature equal to 72±2°C, followed by storage
for at least six hours at a test temperature equal to -40±2°C. The maximum time interval between test temperature
extremes is 30 minutes. Procedure is repeated a total of 10 times, after which all samples are stored for 24 hours at
ambient temperature (20±5°C).
– P/F = No mass loss beyond allowable limits, no leakage, no venting, no disassembly, no rupture and no fire and if the
open circuit voltage of each battery after testing is not less than 90% of its voltage immediately prior to the test
procedure.

8. Manufacturing That Eliminates Risk & Improves Reliability
8
UN38.3 is Required Before Safety UL/IEC Testing
 Before UL2054 or IEC62133 testing can start. The battery needs to pass UN38.3
 UN38.3 Testing
• T3. Vibration
– Simulates vibration during transportation.
– Eight (8) fully charged batteries, Samples are firmly secured to the platform of the vibration machine. Samples
subjected to a sinusoidal waveform with a logarithmic sweep between 7Hz and 200Hz and back to 7Hz traversed in 15
minutes. The cycle was repeated 12 times for a total of 3 hours for each of three mutually perpendicular axes. One of
the directions of vibration must be perpendicular to the terminal face.
– P/F = No mass loss beyond allowable limits, no leakage, no venting, no disassembly, no rupture and no fire and if the
open circuit voltage of each battery after testing is not less than 90% of its voltage immediately prior to the test
procedure.
• T4. Shock
– Simulates shock impacts during shipping
– Eight (8) fully charged batteries. Samples secured to by a means of a rigid mount which will support all mounting
surfaces. Each sample subjected to a half-sine shock of peak acceleration of 150 gn and pulse duration of 6
milliseconds. Each sample subjected to three shocks in the positive direction followed by three shocks in the negative
direction of three mutually perpendicular mounting positions for a total of 18 shocks.
– P/F = No mass loss beyond allowable limits, no leakage, no venting, no disassembly, no rupture and no fire and if the
open circuit voltage of each battery after testing is not less than 90% of its voltage immediately prior to the test
procedure.

9. Manufacturing That Eliminates Risk & Improves Reliability
9
UN38.3 is Required Before Safety UL/IEC Testing
 Before UL2054 or IEC62133 testing can start. The battery needs to pass UN38.3
 UN38.3 Testing
• T5. External short circuit
– Simulates short circuit experienced during transport
– Eight (8) fully charged batteries, samples stabilized to where the external case temperature reaches 57 ± 4°C and then
the sample is subjected to a short circuit condition with a total external resistance of less than 0.1Ω at 57 ± 4°C. The
short condition is continued for a minimum of one hour after the external case temperature has returned to 57 ± 4°C.
The sample is then observed for an additional six hours.
– PF = External temperature does not exceed 170°C and there is no disassembly, no rupture and no fire within six hours
of testing.
• T6. Impact/crush (primary and secondary cells only)
• T7. Overcharge (secondary batteries only)
– Simulates the ability for battery to withstand an overcharge condition during shipping
– Eight (8) previously untested samples. Samples subjected to a charge current of twice the manufacturer’s maximum
charge current and a voltage of lesser of 2x maximum charge voltage at ambient temperature for a total of 24 hours.
– P/F = No disassembly and no fire within seven days of the test.
• T8. Forced discharge (primary and secondary cells only)

10. Manufacturing That Eliminates Risk & Improves Reliability
10
Cells and Batteries Safety Regulations
 IEC 60086-1 Primary batteries – Part 1: General
 IEC 60086-4 Primary batteries – Part 4: Safety of lithium batteries
 IEC 60086-5 Primary batteries – Part 5: Safety of batteries with aqueous electrolyte
 IEC 61056-1 General purpose lead-acid batteries (valve-regulated types) - Part 1: General
requirements, functional characteristics - Methods of test
 IEC 61951-1 Secondary cells and batteries containing alkaline or other non-acid electrolytes –
Portable sealed rechargeable single cells – Part 1: Nickel-cadmium
 IEC 61951-2 Secondary cells and batteries containing alkaline or other non-acid electrolytes –
Portable sealed rechargeable single cells – Part 2: Nickel-metal hydride
 IEC 61960 Secondary cells and batteries containing alkaline or other non-acid electrolytes.
Secondary lithium cells and batteries for portable applications
 IEEE 1725 Standard for rechargeable batteries for cellular telephones (although the standard covers
cellphone batteries, its requirements are applicable to all lithium ion cells and it has the support of
major suppliers of lithium-ion cells)
 ISO 14971 is the standard for risk management in the development of medical devices

11. Manufacturing That Eliminates Risk & Improves Reliability
11
Design Features To Meet
Regulatory Requirements

12. Manufacturing That Eliminates Risk & Improves Reliability
12
Secondary Safety Background
 When and why are secondary safeties used?
– Required for Medical
• UL60601 uses UL2054
 Required for Information Technology, IT
– UL60950 uses UL2054

13. Manufacturing That Eliminates Risk & Improves Reliability
13
Secondary Safety Background (continued)
 What is Secondary Safety? UL2054 (protects against single point failure)
– A secondary safety is exactly what it sounds like it is: a secondary safety.
It is secondary to the primary safety, which is fully independent.
– The primary safety handles all the basic safety functions: over-voltage,
under-voltage, over-current, and sometimes over and under temperature.
– The purpose of the secondary safety is to protect the cell from overcharge
in the event the primary safety circuit fails.
– If the primary charge FET is shorted AND the input charge voltage too
high. The cell can be exposed to an over-charge condition.

14. Manufacturing That Eliminates Risk & Improves Reliability
14
Secondary Safety Background (Continued)
 This is very unlikely to happen, but it can happen if the end user inadvertently plugs in
the wrong battery charger and the primary safeties fail.
 In the unlikely chance all these events happen, the secondary protection would prevent
over charging the cell by breaking the charge current path.

15. Manufacturing That Eliminates Risk & Improves Reliability
15
Use a FET Switch
 Electronically Tripped
– Latching or non-latching
* N-channel FET requires charge pump

16. Manufacturing That Eliminates Risk & Improves Reliability
16
When Should FETs Be Considered as an Alternative to a
Chemical Fuse?

17. Manufacturing That Eliminates Risk & Improves Reliability
17
What if I have a cost sensitive product?
 Rely on the cell’s safeties to prevent excessive overheating.
 Many cells have internal protection.
– Heat and/or pressure detection required.

18. Manufacturing That Eliminates Risk & Improves Reliability
18
Relying on the internal CID
 CID relies on internal cell pressure to activate.
– Most CIDs are not resettable.

19. Manufacturing That Eliminates Risk & Improves Reliability
19
Use TCOs
 More common in single-cell applications.
 Heat detection required.
 Thermal lag can be an issue.

20. Manufacturing That Eliminates Risk & Improves Reliability
20
Design Features To Meet
Regulatory Leakage Requirements

21. Manufacturing That Eliminates Risk & Improves Reliability
21
Reducing Leakage Currents
 IEC60601 requires low leakage currents when
charging battery near a patient
– If connected to the mains
• While connected to patent, low leakage/ high
isolation medical battery charger and/or power
supply required
• While not connected to patient
– Requires robust Inhibit circuit
• Unique connectors to reduce chance of non-
medical chargers used
• Wireless charging

22. Manufacturing That Eliminates Risk & Improves Reliability
22
Going Beyond Just Meeting Regulatory,
Designing In Features To Mitigate Patient Risk

23. Manufacturing That Eliminates Risk & Improves Reliability
23
Smart Batteries Can Help Mitigate Patient Risk
 A smart battery is considered a battery that includes self-monitoring circuitry
 Useful battery data and control
– Authentication check and battery activation SHA-1/HMAC-based
– Wrong battery being used for product detection using SN.
– The battery can provide end-of-useful-service-life data, so it can be taken out of
service before the battery is no longer able to provide sufficient power to operate
the device safely with defined parameters.
• Useful voltage or capacity
– Abnormal internal battery parameters
detected and reported
– Maximum cycle life limit reached
– Passed set expiration date
– Any important for a recall

24. Manufacturing That Eliminates Risk & Improves Reliability
24
Other Features To Mitigate Patient Risk
 Unified system design approach. Medical product, power supply, and
battery need to be designed as a single system
– Impact on location of battery within product
– Cell internal impedance matched with load
– Derating for extreme operating and
environmental conditions
• Cell heaters for extreme low temperatures
• Military and EMS applications

25. Manufacturing That Eliminates Risk & Improves Reliability
25
More Features To Mitigate Patient Risk
 More patients are injured by the incorrect use of a medical device than the
failure of the device itself.
 Design in fool-proof features
– Better capacity and safety reporting
– Unique mating connectors
 The manufacturer should provide sufficient information on how to use the
equipment safely which includes:
– Battery voltage
– Battery type, model number
– Mark connections to prevent incorrect fitting
– Instruct on how to connect and disconnect the battery
– Maintenance required for batteries, chargers, cables, and connectors
– How often to charge batteries based on conditions of use or storage
– When to replace batteries

26. Manufacturing That Eliminates Risk & Improves Reliability
26
Transportation Requirement Highlights

27. Manufacturing That Eliminates Risk & Improves Reliability
27
Cells and Batteries Transportation Regulations
 International Civil Aviation Organization, ICAO,
regulations was issued to limit the state of charge for lithium-
ion batteries to a maximum of 30% when shipped separately
from the device
– Rechargeable Battery Association (PRBA) states that there is
no single method to estimating the state of charge (SOC) of a
lithium battery or cell
 International Air Transport Association (IATA) Dangerous
Goods Regulations (DGR)
 UN38.3, United Nations recommendations on the Transport
of Dangerous Goods Manual of Tests and Criteria
As of Nov. 4, 2020, 300 air/airport
incidents involving lithium batteries carried
as cargo or baggage that have been
recorded since Jan. 23, 2006.

28. Manufacturing That Eliminates Risk & Improves Reliability
28

29. Manufacturing That Eliminates Risk & Improves Reliability
29
Summary

30. Manufacturing That Eliminates Risk & Improves Reliability
30
Summary
 Primary differences between medical batteries and standard off-the-shelf
batteries.
– Manufacturing controls, traceability, added protection
 Design to meet regulatory requirements
– Secondary protection, leakage currents
 Going beyond just meeting regulatory, designing in features to mitigate patient
risk
– Use battery data to preempt battery failures
– Match the system with the battery to create a unified power system
 Transportation, batteries must pass UN38.3
– Pay close attention to 100Wh limit on batteries shipped by air
• Two independent batteries can be in the same enclosure

31. Manufacturing That Eliminates Risk & Improves Reliability
31
Our Products
Battery Packs Flex & Rigid-Flex PCBs Cable Assemblies Printed Circuit Boards
RF Products User Interfaces Flexible Heaters EC Fans & Motors

32. Manufacturing That Eliminates Risk & Improves Reliability
32
Q&A
 Questions?
– Enter any questions you may have
in the control panel
– If we don’t have time to get to it, we
will reply via email

33. Manufacturing That Eliminates Risk & Improves Reliability
33
Thank You
Check out our website at www.epectec.com.
For more information email sales@epectec.com.
Stay Connected with Epec Engineered Technologies
Follow us on our social media sites for continuous technical updates and information: