Safety on Lithium-Ion Batteries

Safety on Lithium-Ion Batteries 

Lithium-ion batteries were developed in the 1970s and first commercialized by Sony in 1991 for the company’s handheld video recorder. Today everything you see is powered by batteries from smartphones, laptops, scooters, e-cigarettes, smoke alarms, toys even the International Space Station, which makes increased battery safety all the more crucial.

In 2008, Tesla unveiled the Roadster making it the first car company to commercialize a battery-powered electric vehicle. By 2025, the global lithium-ion (Li-ion) battery market is expected to reach USD 100.4 billion, over 50% of which will be used for the automotive market.

NFPA 704 rating of a lithium ion batteries marked 010. Other battery chemistries may have 000 or different designations.

NFPA 704 fire diamond for Li-ion batteries

Flammability
Red 0	Material does no burn under normal conditions
Red 1	Material needs considerable preheating before ignition or combustion occurs
Red 2	Material needs moderate heat before ignition or combustion occurs
Red 3	Liquids and solids can be ignited under ambient temperature
Red 4	Vaporizes under atmospheric pressure; burns easily
Health
Blue 0	Poses no health hazard
Blue 1	Exposure causes irritation
Blue 2	Intense and continued use cause injury
Blue 3	Short exposure causes injury
Blue 4	Short exposure causes major injury or death
Reactivity
Yellow 0	Stable
Yellow 1	Becomes unstable at elevated temperature
Yellow 2	Violent changes at high temperature, reacts with water
Yellow 3	Can detonate with trigger
Yellow 4	Can detonate at normal temperature

Lithium-Ion refers to a family of Lithium-based battery technology. This family includes several sub-families or technologies, such as:

·        LCO: Lithium Cobalt Oxide

·        NCA: Nickel Cobalt Aluminium

·        NMC: Nickel Manganese Cobalt

·        LiFePO4 or LFP: Lithium Iron Phosphate

·        LTO: Lithium Titanate Oxide, etc…………..

Often, we can hear that a product is equipped with “Lithium-Ion” batteries, this does not really have any meaning on the technology used. However, out of habit, the technology referred to as Lithium-Ion is usually LCO, NCA or NMC

Each of these technologies has very different characteristics, particularly in terms of safety.

Lithium-ion batteries are popular because of how much power they can put out at a given size and weight. A typical lithium-ion battery stores 150 watt-hours of electricity in 1 kilogram of battery, compared to NiMH Battery pack (100 watt-hours per kg) or Lead Acid Battery (25 watt-hours per kg). It takes 6 kilograms to store the same amount of energy in a lead-acid battery that a 1-kilogram lithium-ion battery can handle.

However, lithium-ion batteries are extremely sensitive to high temperatures and inherently flammable. These battery packs tend to degrade much faster than they normally would, due to heat. If a lithium-ion battery pack fails, it will burst into flames and can cause widespread damage. This calls for immediate measures and guidelines for battery safety. LCO and NCA are the most dangerous chemicals from a thermal runaway point of view with a temperature rise of about 470°C per minute. In addition, it can be seen that LiFePO4 – LFP technology is slightly subject to thermal runaway phenomena, with a temperature rise of barely 1.5°C per minute.

A lithium-ion battery pack consists of lithium-ion cells stacked together in modules, temperature sensors, voltage tap and an on-board computer (Battery Management System) to manage the individual cells. Like any other cell, the lithium-ion cell has a positive electrode (cathode), a negative electrode (anode) and a chemical called an electrolyte in between them. While the anode is generally made from graphite (carbon), different lithium materials are used for the cathode – Lithium Cobalt Oxide (LCO), Lithium Nickel Manganese Cobalt (or NMC), etc.

When a charging current is provided to the cell, lithium ions move from the cathode to the anode through the electrolyte. Electrons also flow but take the longer path outside the circuit. The opposite movement takes place during discharge with the result that the electrons power up the application that the cell has been connected to.

When all the ions have moved back to the cathode, the cell has been completely discharged and will need charging.

Now need to know why lithium-ion batteries catch fire

A. Manufacturing Defects

Flaws in production can cause metallic particles (impurities) to seep into the lithium-ion cell during the manufacturing process. Battery manufacturers need to ensure stringently controlled cleanrooms for manufacturing batteries.

Another defect could be the thinning of separators which could prove detrimental in actual use. Cells should undergo strict quality-control tests and validation before being sold.

B. Design Flaws

Car companies want to design their cars as sleek and slim while giving the maximum range and performance. These requirements push battery pack manufacturers to come up with compact designs by packing high-capacity cells into a smaller body, messing with an otherwise well-built battery.

Compromising on the design can cause damage to the electrodes or the separator. Either of which could result in a short circuit. Further, the absence of a proper cooling system or vent can cause battery temperatures to rise as the flammable electrolyte heats up.

If uncontrolled, it could result in a chain reaction of cell failures, causing the battery to heat up even more and spiral out of control.

C. Abnormal or Improper Usage

External factors like keeping the battery very close to a heat source or near a fire can cause it to explode. Penetrating the battery pack either deliberately or through an accident is bound to cause a short circuit and the battery to catch fire. That’s why unauthorized disassembly of the battery pack in electric vehicles leads to the lapse of warranty.

Users are advised to only get the batteries checked and repaired from the car maker’s authorized service centers. Even high-voltage charging or excessive discharging of the battery could damage it.

D. Charger Issues

Using poorly insulated chargers can damage the battery. If the charger shorts or generates heat near the battery, it can do enough damage to cause failure.

While lithium-ion batteries have built-in protections to stop them from overcharging, using unofficial chargers can damage the battery in the long term.

Do not charge a device under your pillow, on your bed or on a couch.

E. Low-quality components

In addition to manufacturing defects, using low-quality components is one of the highest causes of battery failures. Increasing competition is driving the prices of batteries down, causing battery manufacturers to cut corners where they shouldn’t. By skimping on poor quality electronics like the battery management system, the risk of battery failure increases.

What to do when a battery catches fire?

If you notice the lithium-ion battery overheat, try moving the device away from flammable materials and cutting of the current supply. If you’re in an electric vehicle, you should immediately evacuate and never attempt to extinguish lithium battery fires yourself. Your health and safety are far more important, call the emergency services instead.

In case of fire,  a standard ABC or BC dry chemical fire extinguisher must be used since these are considered Class B fire. A common misconception is that lithium-ion batteries contain any actual lithium metal. They don’t and that’s why you shouldn’t use a Class D Fire Extinguisher. 

There are new and improved methods to douse lithium fires as well. The Aqueous Vermiculite Dispersion (AVD) is a fire extinguishing agent that disperses chemically exfoliated vermiculite in the form of a mist. However, larger lithium-ion fires as that of EVs or ESS may need to burn out. Using water with copper material is effective but is costly.

Like thermal runaway, Lithium-ion cells have a different level of safety depending on the shocks or mechanical treatments they may undergo during their lifetime.

The nail penetration test is the most revealing way to qualify the safety of a cell technology.

The test presented below is performed by perforating a Lithium Ion NMC cell and a Lithium Ion LiFePO4 cell.

We find here the same extremely stable behavior of Lithium Iron Phosphate cells while the NMC cell ignites almost immediately.

Battery Safety experts advise using water even for large lithium-ion fires. Fires like these may burn for days and it’s important to isolate them from flammable materials and prevent them from expanding.

Purchase and use devices that are listed by a qualified testing laboratory. Always follow the manufacturer’s instructions.

Do not put Lithium Iron batteries in the trash. — recycling is always the best option. — take them to a battery recycling location or contact your community for disposal instructions.

How To Maintain Your Sump Pump

How To Maintain Your Sump Pump 

Sump pumps are your first line of defence to keep water out of your basement. They also protect your foundations and the structural integrity of your building. Sump pump maintenance will take no more than around 10 minutes to complete and you will need to check the operation of your sump pump and ensure it is there for you whenever you need it.

Tips for sump pump maintenance

Keep a cover over the sump basin.

• This will keep out animals and children as well as ensuring you do not have any debris falling into the basin.
• A cover will also reduce the smells and evaporation

Inspect for debris

Inspect the basin/sump for any debris and remove any you might find before operating the pump. We do not want this to get into the sump pump intakes or even block the pump. So, always ensure you remove the debris first before you test the pump.

Check pump screens/ Inlet screens

Check the inlet screens on your pump are free from debris and residue build up, as if they are blocked up this will reduce the operational efficiency of your sump pump. This will reduce the volume of water the pump removes. If needed bring a hose and wash down the externals of the sump pump as well as the basin to remove all debris that may affect the operation of the pump.

Electricity and safety

As there is electricity and water within the same installation you should ensure you are electrically protected using a ground fault indicator (GFI). This should keep you safe as it should trip the electricity if there is a fault. Check the operation of this if there is a test facility to do so.

Cable routing

Check for correct cable routing as well as the cable being in good condition. Make sure the cable is away from the water as much as possible. Also check the cable is secured and not loose and in a situation where it might fall into the sump. This could prove lethal and have happened in some rare circumstances. So check the cable is fixed and secure.

Check your discharge pipes

Always have a check valve fitted, this is to stop the pumped water within the discharge pumped line from returning into the sump and refilling the sump once pumped away. It only allows the water to move in one direction, which of course is out of your sump. If this is faulty you will see your sump re-filling and your pump will run more frequently.

Check the discharge line for leaks or damage. Make sure all is intact including the end of your pumping line. If you are able to visually see the pumped line ensure the end is free to allow the pumped water to properly run clear.

Water test your pump

Fill the sump with water very slowly and observe the operation of the sump pump. This way you can watch the operation of the float switch, ensure it rises with the water level and moves easily and freely.

Check the operation of the float switch

Once the float rises to the switch on point you want to observe the sump pump running. You should of course listen to the pump as well. What you are listening for in this case is the connection of the float switch and that the switch makes without any hesitation or resistance and runs the pump properly. As the float switch is considered one of the weak points of a sump pump you can observe this in this test and ensure your switch operates normally. If the switch is intermittent or not operating normally you may be able to replace the switch and not need to buy a replacement sump pump.

Listen to the pump

Now the pump is running you want to listen to the pump itself running. Make sure there are no squealing or grinding noises or even metal on metal. With the sump pump running there should be some minor vibrations, if there are excessive vibrations then you must investigate this. Excessive vibration or noises may indicate the bearings or internal workings of the pump may be wearing out. In cases like this it might be best to have a replacement sump pump near hand in case you have to replace a pump in a hurry.

Operate the pump several times

Operate the pump like this several times just to get the pump operating efficiently and also check that the sump pump also stops pumping whenever the water level is pumped down to a suitable level and the switch has returned to a resting position. In general what you are doing is checking complete cycles of the sump pump to check it is working as it should do when it might be needed.

Check Valve operation

Listen for the check valve click as well within this operation sequence; you want to hear the check valve operating as the pump stops pumping. The check valve should close with a click and stop the water from returning into the sump.

Points to consider for the maintenance of your sump pump and pump installation

·        Keep a cover over the sump basin.

·        Inspect for debris

·        Check pump screens/ Inlet screens

·        Electricity and safety

·        Cable routing

·        Check your discharge pipes

·        Water test your pump

·        Check the operation of the float switch

·        Listen to the pump

·        Operate the pump several times

·        Check Valve operation

·        Replace all covers and parts

Once you are happy with the operation of your sump pump and you have checked everything over you need to ensure you replace all parts and covers into their correct location for the operation of the pump.

You should also periodically check in on your sump pump just to ensure it will be there for you whenever needed.

Pump maintenance entails a number of procedures, most of them simple yet  important, that must be performed before and after use. Depending on how often and how much they’re used, full service maintenance will need to be undertaken.

Pump Inspection, repair and replacement should only be carried out by NFPA certified servicing person from related product company. But there are some simple checks you can do to save disruptive down time and thousands of dollars in pump replacement or repairs.

·        Check pump for noisy bearings and cavitation.

·        Check for unusual vibration.

·        If applicable, check bearing oil for water and discoloration.

·        Feel all bearings for temperature.

·        Inspect bearings and oil rings through filling ports, if 

·        Check oil leaks at the gaskets and flanges

Since some pumps are used in environments where poor performance could pose a risk, it’s absolutely necessary that any pump work is performed by experts.

Calibration: Periodic calibration to ensure that flow rate is according to specifications is one of the to-do’s in maintenance. Failure to do so can result in pump performance being adversely affected and may even lead to accidents. Keeping track of any changes in the pumping system’s performance also aids in making sure pumps work properly.

Checking pump drive system: Pumps driven by motors, either diesel or electrical power, are prone to changing with the temperature. So, cold days will see pump function drop because the depending on the fluid being pumped and if diesel driven the viscosity of the fuel. The same applies to high temperature. Required adjustments, therefore, must be made prior to powering up the system and observing the pump monitoring system and checking the connections and pipework for cracks, leaks and breaks should also be carried out.

Checking the fittings: Daily inspection or prior to use of parts which include mounting feet, nuts, bolts, gaskets, flanges and similar hardware throughout out the system for damage or malfunction. Battery cables, wiring, fans and belts should be inspected too. 

Checking the suction and discharge hoses or pipes: Since all fluids to be removed is done through hoses and/or pipework, doing regular checks on them prior to use and while in use is necessary. Some hoses and pipelines will need to comply to various standards and guidelines relating to their use and testing, but generally should be inspected to suit the conditions of use. Clamps and fastener points should also be checked.

There are many, many types of pumps. It’s a long list. Each industry has need for specific models and together, they cover a vast range. Maintenance requirements are therefore, different, so what’s meant for a gear pump, for example, may not be suitable for a syringe pump.

Since the maintenance requirements for various types of pumps vary, leaving the work to maintenance experts can mean cost-effectiveness and less room for error.

At Complete Fire and Pumps we have a team of dedicated experts with full servicing capabilities on-site, or off, with our fully equipped service vehicles and state of the art pump service centre. To ensure your pumping system remains online and performing at optimum capacity, contact us today!