Health and Safety

This page is aiming to raise your awareness of just few things out of many you should be aware to protect yourself, people around and property.

Your safety is your own responsibility. Whatever you do, if something goes wrong there is no one to blame except yourself.

It is always better to prevent accidents from happening rather than hoping for the best and having the ambulance below the cliff scenario as a result.

If there is a tiny little doubt or uncertainty going through your mind, even for a fraction of a second, that what you are planning to do might not be safe – stop immediately – you should not attempt to do it! You should better let professionals to do the job.

Any work involving high voltage battery pack has associated hazards and risks of being injured or killed. Those hazards may be related to vehicles where batteries are installed, batteries themselves, equipment, tools and work environment.

Health and Safety is of paramount importance to us. We want you to be safe. We want to encourage you to take responsible steps to make sure that you, people around and property are safe when you are dealing with batteries, hybrid or electrical vehicles, or battery testing equipment.

High voltage which is present in Hybrid and Electrical Vehicles and High Voltage Battery Packs is hazardous and could cause death or serious injury!

Extreme care and right procedure has to be undertaken when dismantling the battery from the vehicle, servicing it, or putting it back.

Hybrid or Electrical vehicle may utilize high voltage capacitors which keep charge for some time after the ignition was turned off. That high voltage could be present for a while on the contacts connected to the Battery Pack. In other words a vehicle itself apart from the Battery Pack is a source of High Voltage after ignition is cut-off.

Check and always make sure there is no High Voltage presence in the circuitry connected to the battery pack before disconnecting the battery from the vehicle. That circuitry should be marked in bright orange or red color to be highly visible.

The other risk is associated with the Battery Pack weight. It is heavy and may cause injury if dropped. E.g. Battery Pack from Prius NHW-11 weight is over 45 kg, NHW-20 is over 30kg!

Wear hard-top protective shoes. No sneakers, jandals or bare foot!
Wear High Visibility Vest and a Hard Hat when in the wreck yard:
Hard Top Boots, Hi-Visibility West and Helmet

When dismantling the Battery Pack there is a risk of Electric Shock or Fire if it is done unprofessionally and without following correct procedures.

You would need to have good quality, undamaged High Voltage Electrical Insulating Gloves (depending on the job you are doing up to 500Volts or even up to 1000 Volts). You may also need overalls gloves to protect Electrical Gloves from the sharp objects.
Electrical Insulating Gloves Class 00
Use Specialised Insulated Sockets:
Insulating Sockets up to 1000V
Keep fire extinguisher handy at all times.

Battery Pack should have special Plug (bright Orange). When plug is removed it breaks the continuity of the internal circuitry inside the pack. Remove the plug before dismantling the battery from the vehicle:

Service Plugs – Nissan Leaf, Toyota, Lexus

Battery Pack may have couple of cut-off relays one for the positive and one for the negative output. That is protective circuitry to ensure the high voltage is not present on the output connectors of the pack when vehicle is not operating or the pack is in the storage.

Design of those relays and their position inside the pack could vary.

If the pack enclosure is opened those relays are no longer protect you from being electrocuted as other contacts become exposed and high voltage could be present on those.

Pay attention to every move you make and what you touch and where your tools are when working inside the opened battery pack!
NHW-11 Battery Danger Sign
HW-11 Battery Danger Sign
You should not smoke or use open fire or welding device close to the batteries.
Do not use flammable liquids around the batteries – accidental spark can cause fire.
Use tools with electrically isolated handles.

Never use tools (e.g. metal wrenches) which could short-cut side connectors of the batteries. Resulting current could melt the metal parts, it can cause electrical shock, sparks could cause fire and melted pieces of metal cause skin or eye burns.

Shield eyes with protective goggles.

HiMH batteries contain chemicals. Those chemicals if spilled out from the battery need to be neutralized. Keep Boric Acid handy to neutralize spills.

Do not charge Prismatic Batteries uncompressed. Those could bulge and blow while charging.
Transportation of the batteries should be delegated to professionals who specialize in transportation of hazardous materials. For Ni-MH Batteries refer to recommendations Class 9 UN3496 – Miscellaneous Dangerous Substances.
Do not send batteries in the normal postage or ask anyone to send those to you via normal postage – you put passengers of the commercial flight at risk!
Discharge batteries completely before putting into waste to avoid shortcut and fire!
NHW-10/11/20 Batteries have exposed contacts on both sides

There will always be some other hazards which are not listed above or we might be unaware of.

Please be vigilant and always wear Personal Protective Equipment (PPE), look out for potential hazards, search for more information on health and safety, carefully read guidelines, procedures and manuals coming with tools or equipment you are planning to use.