Hybrid Battery Test

NiMH

Ford Fusion / Mercury Milan / Lincoln MKZ Hybrid NiMH Battery (2010-2012)

The Ford Fusion / Mercury Milan / Lincoln MKZ Hybrid NiMH Battery (2010-2012) is the high voltage battery in the Ford Fusion Hybrid (2010-2012), Mercury Milan Hybrid (2010-2011), Lincoln MKZ Hybrid (2011-2012).

At a Glance

  • NiMH chemistry
  • 275 volts nominal

Specifications

ChemistryNiMH
Cell makerSanyo
Nominal voltage275 V
Capacity5.5 Ah
LocationTrunk, behind the rear seatback (service disconnect behind rear seat)

Cars That Use It

  • Ford Fusion Hybrid 2010-2012 2.5L Atkinson I4 Run the checklist
  • Mercury Milan Hybrid 2010-2011 Run the checklist
  • Lincoln MKZ Hybrid 2011-2012 fueleconomy.gov also lists a 2013 MKZ Hybrid as 275V Ni-MH (likely data carry-over; 2013 Fusion/MKZ ERG describes a lithium pack) Run the checklist

What Goes Wrong

Reported failures, each from a source listed below, as of October 7, 2026.

  • Owner complaints NHTSA lists under the Hybrid Propulsion System component for the Ford Fusion Hybrid, Mercury Milan Hybrid, by model year: 2010: 1 · 2010: 2 · 2011: 1. These are all hybrid system complaints, owner reported and unverified, not only battery faults, as of 2026-10-07.

Warranty

Ford's 2010 Ford and Mercury Hybrid and 2012 Ford Hybrid warranty guides, and the 2011 Lincoln Hybrid warranty guide, list Hybrid Unique Component Coverage of 8 years or 100,000 miles, whichever comes first, covering the high-voltage battery (plus, for Fusion/Milan, the battery pack fan, HBPSM and BECM); the guides add 10 years/150,000 miles for the high-voltage battery on vehicles certified as AT PZEV and registered in states that adopted that California warranty. (fordservicecontent.com: 10hybwa2e.pdf, 2026-10-07)

How battery warranties work.

Get This Pack Tested

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Sources

  1. avt.inl.gov: fact2010fordfusion.pdf
  2. avt.inl.gov: batteryfusion4699.pdf
  3. energy.gov: batteryfusion4699_0.pdf
  4. ford.com: 2010_Fusion_Milan_Hybrid_Emergency_Response_Guide_v0725.pdf
  5. ford.com: firstresponder
  6. fueleconomy.gov: vehicles.csv.zip
  7. fordservicecontent.com: 10hybwa2e.pdf
  8. fordservicecontent.com: 12hybwa2e.pdf
  9. fordservicecontent.com: 11zhywa1e.pdf
  10. NHTSA complaints, 2010 Ford Fusion+Hybrid
  11. NHTSA complaints, 2011 Ford Fusion+Hybrid
  12. NHTSA complaints, 2010 Mercury Milan+Hybrid

Last updated October 7, 2026. Failure and recall notes are as of that date. Spotted a mistake, or speaking for a maker? Report an error.

Hybrid Battery Test is independent. It is not affiliated with, sponsored by or endorsed by Ford, Lincoln, Mercury, Sanyo. Names and part numbers are used only to identify the vehicle and the part.