Spot a Swelling or Failing Battery and Know When to Retire It

Why this happens

Lithium cells can produce gas inside when they are damaged, overcharged, deeply discharged, overheated or simply worn out, and this makes the cells or the pack case bulge. Swelling, unusual heat or smell mean the cells are no longer stable and the risk of a fire rises. Early detection lets you isolate the pack before it becomes dangerous.

What you need

Step by step

1. 1

   Look at the pack from all sides

   With the vehicle switched off, look at the battery or battery compartment in good light. Check for a bulging case, lids that no longer sit flat, seams that have split, a cover or seat that has become hard to close, or a battery that no longer slides easily in and out of its dock. Photograph anything unusual so you can compare later and show the service centre.

2. 2

   Check flatness with a straight edge

   On a removable pack, lay a ruler across each flat face of the case. A gap in the middle, or the ruler rocking on a raised centre, suggests swelling. Do not press, squeeze or tap the case to test it. Only look and measure from the outside, and never open the case to look at the cells.

3. 3

   Use your nose and hands carefully

   A sweet, solvent-like or burning smell near the battery is a warning sign. With your palm held near, not pressed against, the case, check for heat when the vehicle has been parked for a while. A battery that is warm while resting, or much warmer on one side, is abnormal. An infrared thermometer gives you a number to compare between sides.

4. 4

   Notice behaviour changes

   Think about recent behaviour: sudden loss of range, the gauge dropping from a reasonable level to empty, the vehicle cutting out under acceleration, the charger finishing very quickly or never finishing, or frequent error codes about the battery. Any of these alone may have another cause, but combined with physical signs they point to a failing pack.

5. 5

   If you see swelling, stop using it

   Do not charge, ride or try to discharge a swollen battery. If the pack is removable and not hot, carefully move it outdoors to a clear non-flammable spot away from vehicles, buildings and people, and do not put it in water or a closed container. If it is fixed in the vehicle, move the vehicle outdoors away from buildings if it is safe to do so, and contact the manufacturer or authorised service centre.

6. 6

   Know the emergency signs

   Smoke, hissing, popping, sparks or rapidly increasing heat mean a fire may be starting. Move everyone away, do not try to handle the battery, and call the fire service on 112. Lithium battery fires can reignite and release toxic smoke, so do not attempt to put it out yourself beyond keeping people clear.

7. 7

   Retire it through the proper route

   A swollen or failed pack cannot be repaired safely at home. Return it to the dealer, the manufacturer's service network or an authorised battery recycler, as required under India's battery waste rules. Never throw lithium batteries into household waste or sell them to informal scrap dealers who may open them. Keep warranty paperwork and photos; swelling within the warranty period may be covered.

How to tell it worked

You can recognise swelling and failure signs early, isolate a suspect pack safely outdoors and hand it to the right people for diagnosis, warranty or recycling.

Questions