Hybrid Battery Test

Li-ion polymer

Hyundai Ioniq Plug-in Hybrid / Kia Niro Plug-in Hybrid 8.9 kWh Battery

The Hyundai Ioniq Plug-in Hybrid / Kia Niro Plug-in Hybrid 8.9 kWh Battery is the high voltage battery in the Hyundai Ioniq Plug-in Hybrid (2018-2022), Kia Niro Plug-in Hybrid (2018-2022).

At a Glance

  • Li-ion polymer chemistry
  • 360 volts nominal

Specifications

ChemistryLi-ion polymer
Nominal voltage360 V
Capacity24.7 Ah
Energy8.9 kWh
Locationunder the rear seats (Ioniq)
Weight117 kg

Cars That Use It

  • Hyundai Ioniq Plug-in Hybrid 2018-2022 AE; 45 kW motor Run the checklist
  • Kia Niro Plug-in Hybrid 2018-2022 DE; Kia spec 360V, 24.7 Ah, 8.9 kWh, 59 kW, 258 lb Run the checklist

Recalls

  • 18V704000 2018 (Ioniq Plug-in Hybrid) The main relay in the Power Relay Assembly may have poor connections between its contacts, raising electrical resistance.
  • 22V459000 2018 (Ioniq Plug-in Hybrid) The Power Relay Assembly under the rear seat may overheat, on cars previously recalled under 18V-704.

Check the exact car by VIN at nhtsa.gov/recalls.

Warranty

Hyundai's 2021 Warranty Coverage Guide lists lifetime battery coverage for the original owner of 2018-2019 Ioniq Plug-in Hybrids, 10 years/100,000 miles from 2020 models, and 10 years/150,000 miles on the battery for 2018-2021 cars certified SULEV/PZEV/TZEV in California-emission states, Hyundai's 2022 Owner's Handbook lists 10 years/100,000 miles (10 years/150,000 miles for the 2022 Ioniq Plug-in Hybrid battery when certified TZEV), and Kia's 2018 Niro Hybrid and Plug-in Hybrid manual lists the Hybrid Battery Pack under a 10-year/100,000-mile Hybrid System Warranty; Niro PHEV 2019-2022 terms were not confirmed. (static.nhtsa.gov: INRD-PE21010-15928.pdf, 2026-10-07)

How battery warranties work.

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Sources

  1. hyundainews.com: 30726-2018HyundaiIoniqPluginHybridRelease1222172.pdf
  2. hyundainews.com: 33114-2019IoniqSpecificationsPPReviewFINAL.pdf
  3. hyundainews.com: 42765-2021IoniqProductGuideSpecs.pdf
  4. kiamedia.com: specifications
  5. kiamedia.com: specifications
  6. greencarreports.com: 1108840_2017-hyundai-ioniq-to-have-lifetime-battery-failure-
  7. hyundaiusa.com: america-best-warranty
  8. kia.com: warranty
  9. static.nhtsa.gov: INRD-PE21010-15928.pdf
  10. hyundaiusa.com: 2022_Owners_Handbook_Warranty.pdf
  11. kia.com: 2018_warranty_niro_hybrid_and_plug_in_hybrid.pdf

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 Hyundai, Kia. Names and part numbers are used only to identify the vehicle and the part.