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Electrical Energy Storage Unit and Control System and Applications Thereof

US 9,331,497 In force
OverviewFamilyAssignmentsSources & methods

Term ends Aug 5, 2031 · High confidence

Filed Aug 27, 2013 as application 13/978,689 · Granted May 3, 2016
Base term plus 153 days of patent term adjustment (USPTO delay)
Today
20 years from filing
2011 2031
Clock starts
Mar 5, 2011
Term ends
Aug 5, 2031
Granted
May 3, 2016
base term patent term adjustment fee events Updated Nov 14, 2026 · includes USPTO assignment & status data published Nov 14, 2026 and grant & fee data published Nov 10, 2026 (weekly) · how we know
153
Days of term adjustment
Read from the USPTO patent term adjustment record, not recalculated here.
None
Terminal disclaimer
No disclaimer on this record.
2 of 3
Maintenance fees paid
Three maintenance fees fall due, at 3.5, 7.5 and 11.5 years from grant. This counts the ones the record shows paid.
4
Family applications on record here
Applications sharing this one's continuity chain whose file history this site holds. The family may have others.

This patent's term runs 153 days past its 20-year base term on prosecution delay. 2 of 3 maintenance fees are paid so far. Confidence: High. from the record

How we calculated this date

One row per rule, each showing its own input and what it did to the date. A step we could not verify says so instead of resolving itself.
StepInputDate after this stepConfidence
Base term, 20 years from filingClock starts Mar 5, 2011, when application PCT/CN2011/071548, the earliest non-provisional in its chain, was filed (this one was filed Aug 27, 2013)Mar 5, 2031High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustment+153 days, USPTO patent term adjustment recordAug 5, 2031High confidence
Terminal disclaimer capNone on recordno cap appliedHigh confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events2 of 3 maintenance fees paidIn forceHigh confidence
Computed term endThe steps above, in orderAug 5, 2031High confidence

This family

US 9,331,497this patent
Aug 2031
Aug 2031
US 9,847,654In force
no later than Jun 2031
no later than Jun 2031
US 10,536,007In force
Apr 2031
Apr 2031
3 of 4 applications in this family shown, earliest filings first. The applications whose file history this site holds. The family may have others.

Assignments

Assignment documents as recorded at the USPTO, oldest first, with the reel and frame each was recorded at. A recorded assignment is a filed document, not a statement of current ownership, and the absence of a later one is not evidence that the last one still stands.
RecordedAssignorAssigneeConveyance
Jul 8, 2013
Reel 30752, frame 863
Beaston, Virgil LeePowin CorporationAssignment of Assignor's Interest
Dec 10, 2014
Reel 34462, frame 868
Powin CorporationPowin Energy CorporationAssignment of Assignor's Interest
Oct 28, 2019
Reel 50840, frame 901
Powin Energy CorporationArroyo Energy Investment Partners LLCSecurity Interest
Oct 30, 2019
reel/frame not recorded
Powin Energy CorporationPowin Energy Finance LLCSecurity Interest
Oct 30, 2019
reel/frame not recorded
Powin Energy CorporationArroyo Energy Investment Partners LLCSecurity Interest
Oct 30, 2019
Reel 50926, frame 48
Powin Energy CorporationPowin Energy Finance LLC; Arroyo Energy Investment Partners LLCSecurity Interest
Apr 23, 2021
Reel 56024, frame 524
Powin Energy CorporationPowin, LLCAssignment of Assignor's Interest
Jan 3, 2022
Reel 58524, frame 848
Powin, LLCHSBC Bank USA, N.A., as Administrative AgentSecurity Interest
Jan 13, 2022
Reel 58652, frame 252
Arroyo Energy Investment Partners LLCPowin Energy CorporationRelease of Security Interest
Oct 23, 2023
Reel 65310, frame 290
HSBC Bank USA, N.A., as Administrative AgentPowin, LLCRelease of Security Interest
Oct 2, 2024
Reel 69102, frame 539
Powin, LLCGlas USA LLC, as Collateral AgentNotice of Security Interest in Intellectual Property
Sep 24, 2025
Reel 72946, frame 629
Powin, LLCFlexgen Power Systems, LLCAssignment of Assignor's Interest
Oct 10, 2025
Reel 72535, frame 800
Powin, LLC, et Al, Debtors, via U.S. Bankruptcy Court, District of New JerseyFlexgen Power Systems, LLCRelease of Security Interest

Sources

Google Patents · The patent document at USPTO · Assignment records at USPTO

USPTO account required: This application in Patent Center · USPTO's maintenance fee lookup

Maintenance fee events come from USPTO's own fee records. Its fee lookup asks for the patent number and the application number.

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