EnerSys

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 10-K

for the fiscal year ended March 31, 2026 or

Commission file number:001-32253

ENERSYS

(Exact name of registrant as specified in its charter)

2366 Bernville Road

Reading, Pennsylvania 19605

(Address of principal executive offices) (Zip Code)

Registrant’s telephone number, including area code:610-208-1991

Securities registered pursuant to Section 12(b) of the Act:

Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. ý Yes ¨ No

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.¨ Yesý No

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. ý Yes ¨ No

Indicate by check mark whether the registrant has submitted electronically, every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (Section 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ý No¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See definitions of “large accelerated filer,” “accelerated filer”, “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.¨

Indicate by check mark whether the registrant has filed a report on and attestation to its management's assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C 7262(b)) by the registered public accounting firm that prepared or issued its audit report.☒

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐ Yesý No

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b).¨

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). ☐ Yesý No

State the aggregate market value of the voting and non-voting common equity held by non-affiliates at September 28, 2025: $4,153,025,193 (1) (based upon its closing transaction price on the New York Stock Exchange on September 26, 2025).

(1)For this purpose only, “non-affiliates” excludes directors and executive officers.

Common stock outstanding at May 15, 2026:36,517,773 Shares of Common Stock

DOCUMENTS INCORPORATED BY REFERENCE

Portions of the registrant’s definitive Proxy Statement for its Annual Meeting of Stockholders to be held on or about August 6, 2026 are incorporated by reference in Part III of this Annual Report.

CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

The Private Securities Litigation Reform Act of 1995 (the “Reform Act”) provides a safe harbor for forward-looking statements made by or on behalf of EnerSys. EnerSys and its representatives may, from time to time, make written or verbal forward-looking statements, including statements contained in EnerSys’ filings with the Securities and Exchange Commission (“SEC”) and its reports to stockholders. Generally, the inclusion of the words “anticipate,” “believe,” “expect,” “future,” “intend,” “estimate,” “will,” “plans,” or the negative of such terms and similar expressions identify statements that constitute “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934 and that are intended to come within the safe harbor protection provided by those sections. All statements addressing operating performance, events, or developments that EnerSys expects or anticipates will occur in the future, including statements relating to sales growth, earnings or earnings per share growth, and market share, as well as statements expressing optimism or pessimism about future operating results, are forward-looking statements within the meaning of the Reform Act. The forward-looking statements are and will be based on management’s then-current beliefs and assumptions regarding future events and operating performance and on information currently available to management, and are applicable only as of the dates of such statements.

Forward-looking statements involve risks, uncertainties and assumptions. Although we do not make forward-looking statements unless we believe we have a reasonable basis for doing so, we cannot guarantee their accuracy. Actual results may differ materially from those expressed in these forward-looking statements due to a number of uncertainties and risks, including the risks described in this Annual Report on Form 10-K and other unforeseen risks. You should not put undue reliance on any forward-looking statements. These statements speak only as of the date of this Annual Report on Form 10-K, even if subsequently made available by us on our website or otherwise, and we undertake no obligation to update or revise these statements to reflect events or circumstances occurring after the date of this Annual Report on Form 10-K.

Our actual results may differ materially from those contemplated by the forward-looking statements for a number of reasons, including the following factors:

•economic, financial and other impacts of the pandemic, including global supply chain disruptions;

•general cyclical patterns of the industries in which our customers operate;

•global economic trends, competition and geopolitical risks, including impacts from the ongoing conflict between Russia and Ukraine and the related sanctions and other measures, tensions across the Middle East, including the conflict with Iran, changes in the rates of investment or economic growth in key markets we serve, or an escalation of sanctions, tariffs or other trade tensions between the U.S. and China or other countries, and related impacts on our global supply chains and strategies;

•the extent to which we cannot control our fixed and variable costs;

•the raw materials in our products may experience significant fluctuations in market price and availability;

•certain raw materials constitute hazardous materials that may give rise to costly environmental and safety claims;

•legislation, regulation, or policy regarding the restriction of the use of energy or certain hazardous substances in our products;

•risks involved in our operations such as supply chain issues, disruption of markets, changes in government priorities or budgets, including, but not limited to, guidance related to Section 45X of the Internal Revenue Code and implementation of grant awards by the U.S. Department of Energy, changes in import and export laws, changes in tariff rates, environmental regulations, currency restrictions and local currency exchange rate fluctuations;

•our ability to raise our selling prices to our customers when our product costs increase;

•the extent to which we are able to efficiently utilize our global manufacturing facilities and optimize our capacity;

•changes in macroeconomic and market conditions and market volatility, including inflation, interest rates, the value of securities and other financial assets, transportation costs, costs and availability of electronic components, lead, plastic resins, steel, copper and other commodities used by us, and the impact of such changes and volatility on our financial position and business;

•competitiveness of the battery markets and other energy solutions for industrial applications throughout the world;

•our timely development of competitive new products and product enhancements in a changing environment and the acceptance of such products and product enhancements by customers;

•our ability to adequately protect our proprietary intellectual property, technology and brand names;

•litigation and regulatory proceedings to which we might be subject;

•our expectations concerning indemnification obligations;

•changes in our market share in the business segments where we operate;

•our ability to implement our cost reduction initiatives successfully and improve our profitability;

•quality problems associated with our products;

•our ability to implement business strategies, including our acquisition strategy, manufacturing expansion and restructuring plans;

•our acquisition strategy may not be successful in identifying advantageous targets;

•our ability to successfully integrate any assets, liabilities, customers, systems and management personnel we acquire into our operations and our ability to realize related revenue synergies, strategic gains, and cost savings may be significantly harder to achieve, if at all, or may take longer to achieve;

•our effective income tax rate with respect to any period may fluctuate based on the mix of income in the tax jurisdictions, in which we operate, changes in tax laws and the amount of our consolidated earnings before taxes;

•potential goodwill impairment charges, future impairment charges and fluctuations in the fair values of reporting units or of assets in the event projected financial results are not achieved within expected time frames;

•our debt and debt service requirements which may restrict our operational and financial flexibility, as well as imposing unfavorable interest and financing costs;

•our ability to maintain our existing credit facilities or obtain satisfactory new credit facilities or other borrowings;

•adverse changes in our short and long-term debt levels under our credit facilities;

•our exposure to fluctuations in interest rates on our variable-rate debt;

•our ability to attract and retain qualified management and personnel;

•our ability to maintain good relations with labor unions;

•credit risk associated with our customers, including risk of insolvency and bankruptcy;

•our ability to successfully recover in the event of a disaster affecting our infrastructure, supply chain, or our facilities;

•delays or cancellations in shipments;

•occurrence of natural or man-made disasters or calamities, including health emergencies, the spread of infectious diseases, pandemics, vaccine mandates, outbreaks of hostilities or terrorist acts, or the effects of climate change, and our ability to deal effectively with damages or disruptions caused by the foregoing; and

•the operation, capacity and security of our information systems and infrastructure.

This list of factors that may affect future performance is illustrative, but by no means exhaustive. Accordingly, all forward-looking statements should be evaluated with the understanding of their inherent uncertainty.

EnerSys

Annual Report on Form 10-K

For the Fiscal Year Ended March 31, 2026

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