Spills - Toyota AVALON Hybrid Dismantling Manual

Spills

The AVALON Hybrid contains the same common automotive fluids used in other non-hybrid
Toyota vehicles, with the exception of the NiMH electrolyte used in the HV battery pack. The
NiMH battery electrolyte is a caustic alkaline (pH 13.5) that is damaging to human tissues.
The electrolyte, however, is absorbed in the cell plates and will not normally spill or leak out
even if a battery module is cracked. A catastrophic crash that would breach both the metal
battery pack case and a metal battery module would be a rare occurrence.
A caustic alkaline is at the opposite end of the pH scale from a strong acid. A safe (neutral)
substance is approximately in the middle of this scale. Adding a weak acidic mixture, such as
a dilute boric acid solution or vinegar, to the caustic alkaline electrolyte will cause the
electrolyte to be neutralized. This is similar but opposite to the use of baking soda to
neutralize a lead-acid battery electrolyte spill.
A Toyota Product Safety Data Sheets (PSDS) is attached to this document.

Handle NiMH electrolyte spills using the following Personal Protective Equipment (PPE):
• Splash shield or safety goggles. A fold down face shield is not acceptable for acid
or electrolyte spills.
• Rubber, latex or nitrile gloves.
• Apron suitable for alkaline.
• Rubber boots.

Neutralize NiMH electrolyte.
• Use a boric acid solution or vinegar.
• Boric acid solution - 800 grams boric acid to 20 liters water or 5.5 ounces boric
acid to 1 gallon of water.
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