The Volts have been around long enough that we have seen several needing cell section replacements due to service life concerns. This vehicle has 123,000 miles on it and has been setting service messages and codes. I diagnosed cell section 3 as needing replacement. Here's a look at the necessary procedures.

The Gen 1 Volt has 288 L.I. cells laser welded in groups of 3 to form 96 cell groups. Battery section 1 has 30 cell groups. Section 2 has 24 groups and section 3 has 42 cell groups. They are set up in a T fashion and cell section 3 is the transverse section. The BECM and 4 interface control modules are attached to the top of the cell sections.

First, we need to remove the HV battery.

[2013 Chevrolet Volt, Engine/Propulsion Photo]

Next, the cover is removed.

[2013 Chevrolet Volt, Engine/Propulsion Photo]

Cell section 3 is the sideways mounted section. Here's the new assembly ready to install.

[2013 Chevrolet Volt, Engine/Propulsion Photo]

First, the HV bus bars, battery hold downs, manual disconnect housing, coolant tubes, wiring harness and the interface control modules need to be removed.

[2013 Chevrolet Volt, Engine/Propulsion Photo]

This cell section is very heavy and unwieldy so a holding fixture is used to remove and install the cell section. Note that the entire HV battery assembly is live under the cover and proper precautions must be followed as fatal voltage is present at all times.

[2013 Chevrolet Volt, Engine/Propulsion Photo]

A chain fall is used to remove and replace the cell section.

[2013 Chevrolet Volt, Engine/Propulsion Photo]

After reassembly, before the cover is installed, the new cell section must be balanced to match the existing other two sections. A special tool must be used along with cables, fuse block and interfaces. The balancing procedure takes 2 to 4 hours and the cover is then installed. There are also adapters to test for coolant leakage as well as adapters to smoke test the battery housing and cover for leakage.

[2013 Chevrolet Volt, Engine/Propulsion Photo]

James from Florida

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