Hybrid Battery Test

Li-ion

Honda Clarity Plug-In Hybrid Battery (17 kWh Li-ion)

The Honda Clarity Plug-In Hybrid Battery (17 kWh Li-ion) is the high voltage battery in the Honda Clarity Plug-In Hybrid (2018-2021).

At a Glance

  • Li-ion chemistry
  • 311 volts nominal
  • 14 modules
  • liquid cooled

Specifications

ChemistryLi-ion
Nominal voltage311 V
Modules14
Energy17 kWh
Coolingliquid (water-cooled IPU, a Honda/Acura first); ERG lists high-voltage battery coolant 1.69 US gal (6.38 L)
Locationunder the cabin (passenger compartment) floor

Cars That Use It

  • Honda Clarity Plug-In Hybrid 2018-2021 US market; 47-mi EPA EV range 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 Honda Clarity Plug-In Hybrid, by model year: 2018: 1. These are all hybrid system complaints, owner reported and unverified, not only battery faults, as of 2026-10-07.

Warranty

Honda's 2018 Clarity Plug-In Hybrid emissions warranty parts list (APL 14156) lists the hybrid battery assembly at 8 years/100,000 miles in all states and 10 years/150,000 miles in California, Connecticut, Delaware, Maine, Maryland, Massachusetts, New Jersey, New York, Oregon, Pennsylvania, Rhode Island, Vermont and Washington; 2019-2021 lists were not opened. (owners.honda.com: 2018_Honda_Clarity_Plug-In_Hybrid_-_APL14156_SIS.pdf, 2026-10-07)

How battery warranties work.

Get This Pack Tested

Do not open it yourself. The pack can hurt you with the car switched off.

Book a battery test Find a tech near you

How to test a hybrid battery safely

Sources

  1. techinfo.honda.com: AEG07616.pdf
  2. hondanews.com: 2018-honda-clarity-plug-in-hybrid-press-kit
  3. owners.honda.com: 2018_Honda_Clarity_Plug-In_Hybrid_-_APL14156_SIS.pdf
  4. NHTSA complaints, 2018 Honda Clarity+Plug-In+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 Honda. Names and part numbers are used only to identify the vehicle and the part.