<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.26.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>81</ContextCount>
  <ElementCount>25</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>false</FootnotesReported>
  <SegmentCount>12</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>1</UnitCount>
  <MyReports>
    <Report instance="tm261518-1_def14a.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>995100 - Document - Cover</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/dei/role/document/Cover</Role>
      <ShortName>Cover</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="tm261518-1_def14a.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>995410 - Disclosure - Pay vs Performance Disclosure</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/ecd/role/PvpDisclosure</Role>
      <ShortName>Pay vs Performance Disclosure</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="tm261518-1_def14a.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>995443 - Disclosure - Award Timing Disclosure</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/ecd/role/AwardTimingDisclosure</Role>
      <ShortName>Award Timing Disclosure</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="tm261518-1_def14a.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>995447 - Disclosure - Insider Trading Policies and Procedures</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/ecd/role/InsiderTradingPoliciesProc</Role>
      <ShortName>Insider Trading Policies and Procedures</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <InputFiles>
    <File>sldp-20251231.xsd</File>
    <File>sldp-20251231_def.xml</File>
    <File>sldp-20251231_lab.xml</File>
    <File>sldp-20251231_pre.xml</File>
    <File doctype="DEF 14A" isProxy="true" isUsgaap="true" original="tm261518-1_def14a.htm">tm261518-1_def14a.htm</File>
  </InputFiles>
  <SupplementalFiles>
    <File>bc_compensation-4c.jpg</File>
    <File>cv_solidpower-4clr.jpg</File>
    <File>cv_solidpowerobc-4c.jpg</File>
    <File>ft_directorsolidpower-4c.jpg</File>
    <File>ft_notice2023-4c.jpg</File>
    <File>ft_solidpower-4c.jpg</File>
    <File>ic_ablue-4c.jpg</File>
    <File>ic_aleksandramiziolek-4c.jpg</File>
    <File>ic_awhite-4c.jpg</File>
    <File>ic_cross-4c.jpg</File>
    <File>ic_datetime-4c.jpg</File>
    <File>ic_erikanderson-4c.jpg</File>
    <File>ic_gwhite-4c.jpg</File>
    <File>ic_gyellow-4c.jpg</File>
    <File>ic_hgreen-4c.jpg</File>
    <File>ic_hwhite-4c.jpg</File>
    <File>ic_i-4c.jpg</File>
    <File>ic_internet-4c.jpg</File>
    <File>ic_johnstephens-4c.jpg</File>
    <File>ic_johnvanscoter-4c.jpg</File>
    <File>ic_kaledawada-4c.jpg</File>
    <File>ic_lesaroe-4c.jpg</File>
    <File>ic_location-4c.jpg</File>
    <File>ic_mail-4c.jpg</File>
    <File>ic_maryannwright-4c.jpg</File>
    <File>ic_n-4c.jpg</File>
    <File>ic_plus-4c.jpg</File>
    <File>ic_rainerfeurer-4c.jpg</File>
    <File>ic_stevengoldberg-4c.jpg</File>
    <File>ic_susankreh-4c.jpg</File>
    <File>ic_vote-4c.jpg</File>
    <File>lg_solidpowernew-4c.jpg</File>
    <File>pc_ceoneo-4c.jpg</File>
    <File>ph_aleksandramiziolek-4c.jpg</File>
    <File>ph_erikanderson-4c.jpg</File>
    <File>ph_johnstephens-4c.jpg</File>
    <File>ph_johnvanscoter-4c.jpg</File>
    <File>ph_kaledawada-4c.jpg</File>
    <File>ph_lesaroe-4c.jpg</File>
    <File>ph_maryannwright-4c.jpg</File>
    <File>ph_rainerfeurer-4c.jpg</File>
    <File>ph_stevengoldberg-4c.jpg</File>
    <File>ph_susankreh-4c.jpg</File>
    <File>px_solidpower2026pg01-bw.jpg</File>
    <File>px_solidpower2026pg02-bw.jpg</File>
    <File>sg_johnvanscoter-bw.jpg</File>
    <File>sg_lindaheller-bw.jpg</File>
    <File>sg_maryannwright-bw.jpg</File>
  </SupplementalFiles>
  <BaseTaxonomies>
    <BaseTaxonomy items="3">http://fasb.org/us-gaap/2025</BaseTaxonomy>
    <BaseTaxonomy items="4">http://xbrl.sec.gov/dei/2025</BaseTaxonomy>
    <BaseTaxonomy items="125">http://xbrl.sec.gov/ecd/2025</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>false</HasCalculationLinkbase>
</FilingSummary>
