Energy Storage Systems & Equipment | Standards Michigan

Energy Storage Systems & Equipment

Visit the IEEE Education & Healthcare Facilities Committee website for more detailed information.


Energy Storage Systems & Equipment

January 1, 2020

The trough battery, which was in essence a Voltaic Pile laid down to prevent electrolyte leakage | CLICK ON IMAGE

Underwriters Laboratories (UL) has launched a new revision cycle for its standard — UL 9540 Standard for Safety for Energy Storage Systems and Equipment —  which sets the standard of care for energy storage systems that are intended to receive electric energy and then to store the energy in some form so that the energy storage system can provide electrical energy to loads or to the local/area electric power system up to the utility grid when needed.   The list of proposed changes to the 2016 edition is lengthy and will be meaningful to electrical storage technologies specified, installed and operated in every industry:

(a) Addition of UL 1973 to Appendix A Component List

(b) Addition of ISO Functional safety standards,

(c) Revision of grounding and bonding system construction,

(d) Revision of the strength of enclosure walls and supports requirements,

(e) References to required signage and instructions,

(f) Deletion of nonmandatory language throughout standard,

(g) Revision of scope language for clarity,

(h) Revisions to the fire detection and suppression section,

(i) Proposed addition of new 32.4.6,

(j) Revision to mechanical tests for clarification,

(k) Clarification of 1.2,

(l) Revision of 6.4, harmonization with other existing standards,

(m) Enclosure materials for outdoor installations,

(n) Short circuit exposure evaluation,

(o) Clarification of scope,

(p) Clarifications of component and normative reference section,

(q) Clarification of corrosion requirements for enclosures,

(r) Revisions to make the use of term “energy storage system” consistent throughout entire standard,

(s) Clarification of instructions for worker safety,

(t) Revisions to clarify intent and application of 11.1 and 12.2,

(u) Clarifications of system requirements for where the system is installed,

(v) Clarification of the intended environment,

(w) Clarification of bonding and grounding requirements,

(x) Clarifications of 17.1 and 18.1,

(y) Clarification of 21.1,

(z) Clarification of 32.2.2,

(aa) Clarification of 40.4 and 40.5,

(ab) Clarification of 11.2,

(ac) Addition of requirements for residential ESS,

(ad) Addition of production checks on electronic controls,

(ae) Addition of requirements for quality control of production,

(af) Additional testing options,

(ag) Addition of a wall mount fixture test for wall-mounted ESS,

(ah) Addition of Normative Appendix D for alternative lead acid or ni-cad battery system evaluation,

(ai) Revision of 12.3 to add short circuit protection,

(aj) Addition of Informative Appendix E for Guidance on Capacity and Separation Distance Limits for ESS,

(ak) Addition of EMC testing,

(al) Revision of utility grid interaction reaction requirements,

(am) Clarification of the scope,

(an) Clarification of Vapor concentration requirements,

(ao) Addition of emergency contact marking,

(ap) Clarification of flame test surface area

aq) Addition of 8.2 and Appendix F 2, Revisions for electrochemical ESS above 20 kWh.

It is easier to work with the strike-and-bold version posted on ANSI’s website so you can see the changes in context.  A new redline was released December 20th; linked below:

ANSI Standards Action Page 52

Comments due January 19th.

The UL landing page for public comment is linked below and where you may obtain an electronic copy for review.

UL Collaborative Standards Development System

Send comments (with optional copy to to: Megan Van Heirseele, (847) 664-2881,

Energy Storage System at the University of Birmingham / United Kingdom

We are happy to discuss this, and any standard any day at 11 AM Eastern time.  We typically collaborate with the IEEE Education & Healthcare Facilities Committee on formulating comments on standards of this nature.   We also set aside an hour every month dedicated to electrical and energy standards.  See our CALENDAR for the next online meeting; open to everyone.


Issue: [19-143]

Category: Electrical, Energy

Colleagues: Mike Anthony, Jim Harvey, Kane Howard, Glenn Keates, Jose Meijer


UL 9540 Overview Energy Storage



Layout mode
Predefined Skins
Custom Colors
Choose your skin color
Patterns Background
Images Background