Battery packs are made from a large number of parts. Often it is not the battery cells that fail and hence a repair or replacement of the failed part is logical.

One of the first steps is diagnosing what has failed or is failing. This might be in a number of ways:

  • customer impact
    • range / power / charging time
    • doesn’t always switch on
    • errors displayed
  • vehicle / system level diagnostics
    • vehicle ECU error codes
    • BMS errors and battery pack data
  • external testing
  • internal / sub-system testing

The next stage is fixing that fault. Again, this might be done in a number of ways from software updates through to complete pack replacement.

Replacing a module / set of cells in a battery pack can have a number of challenges.

Tesla model Y 4680 battery with the top lid removed

The Tesla Model Y battery pack with the 4680 cylindrical cells doesn’t lend itself to being repaired in any way.

The cells are covered in a “silicon” based foam that is designed to reduce the chance of thermal runaway.

4R’s Repair, Reman, Repurpose, Recycle

Before moving to the recycling of a battery the following options should be considered:

  1. Repair
  2. Remanufacture
  3. Repurpose
  4. Recycling

This approach can reduce cost, impact on the customer and most importantly the impact on the planet.

Batteries are not emissions and toxic waste free and so the life cycle analysis (LCA) must be considered from cradle to grave.