<SEC-DOCUMENT>0001562180-24-003162.txt : 20240402
<SEC-HEADER>0001562180-24-003162.hdr.sgml : 20240402
<ACCEPTANCE-DATETIME>20240402163225
ACCESSION NUMBER:		0001562180-24-003162
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20240329
FILED AS OF DATE:		20240402
DATE AS OF CHANGE:		20240402

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Tinnemeyer Joern
		CENTRAL INDEX KEY:			0001911037
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-32253
		FILM NUMBER:		24814825

	MAIL ADDRESS:	
		STREET 1:		C/O ENERSYS
		STREET 2:		2366 BERNVILLE ROAD
		CITY:			READING
		STATE:			PA
		ZIP:			19605

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			EnerSys
		CENTRAL INDEX KEY:			0001289308
		STANDARD INDUSTRIAL CLASSIFICATION:	MISCELLANEOUS ELECTRICAL MACHINERY, EQUIPMENT & SUPPLIES [3690]
		ORGANIZATION NAME:           	04 Manufacturing
		IRS NUMBER:				233058564
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0331

	BUSINESS ADDRESS:	
		STREET 1:		2366 BERNVILLE ROAD
		CITY:			READING
		STATE:			PA
		ZIP:			19605
		BUSINESS PHONE:		(610) 208-1600

	MAIL ADDRESS:	
		STREET 1:		2366 BERNVILLE ROAD
		CITY:			READING
		STATE:			PA
		ZIP:			19605
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primarydocument.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2024-03-29</periodOfReport>

    <notSubjectToSection16>false</notSubjectToSection16>

    <issuer>
        <issuerCik>0001289308</issuerCik>
        <issuerName>EnerSys</issuerName>
        <issuerTradingSymbol>ENS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001911037</rptOwnerCik>
            <rptOwnerName>Tinnemeyer Joern</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ENERSYS</rptOwnerStreet1>
            <rptOwnerStreet2>2366 BERNVILLE ROAD</rptOwnerStreet2>
            <rptOwnerCity>READING</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>19605</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>false</isDirector>
            <isOfficer>true</isOfficer>
            <isTenPercentOwner>false</isTenPercentOwner>
            <isOther>false</isOther>
            <officerTitle>Sr. VP &amp; CTO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>false</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2024-03-29</value>
            </transactionDate>
            <deemedExecutionDate>
                <value>2024-03-29</value>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>false</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3.2526</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>24355.2481</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2024-03-29</value>
            </transactionDate>
            <deemedExecutionDate>
                <value>2024-03-29</value>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>false</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3.8523</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>24359.1004</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2024-03-29</value>
            </transactionDate>
            <deemedExecutionDate>
                <value>2024-03-29</value>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>false</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>11.9112</value>
                    <footnoteId id="F3"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>24371.0116</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2024-03-29</value>
            </transactionDate>
            <deemedExecutionDate>
                <value>2024-03-29</value>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>false</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>11.7768</value>
                    <footnoteId id="F4"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>24382.7884</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">These shares were granted in the form of Restricted Stock Units (&quot;RSUs&quot;), in connection with the cash dividend paid on March 29, 2024 to stockholders of record as of March 15, 2024 (the &quot;Dividend&quot;), with respect to 1,277 unvested RSUs granted to the reporting person on August 17, 2020, and adjusted for previously declared and paid cash dividends. These RSUs will vest and are payable concurrent with the underlying RSUs.</footnote>
        <footnote id="F2">These shares were granted in the form of RSUs, in connection with the Dividend, with respect to 1,525 unvested RSUs granted to the reporting person on August 16, 2021, and adjusted for previously declared and paid cash dividends. These RSUs will be payable concurrent with the underlying RSUs.</footnote>
        <footnote id="F3">These shares were granted in the form of RSUs, in connection with the Dividend, with respect to 4,762 unvested RSUs granted to the reporting person on August 12, 2022, and adjusted for previously declared and paid cash dividends. These RSUs will be payable concurrent with the underlying RSUs.</footnote>
        <footnote id="F4">These shares were granted in the form of RSUs, in connection with the Dividend, with respect to 4,751 unvested RSUs granted to the reporting person on August 11, 2023, and adjusted for previously declared and paid cash dividends. These RSUs will be payable concurrent with the underlying RSUs.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Karen J. Yodis, by Power of Attorney</signatureName>
        <signatureDate>2024-04-02</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
