WHO SHOULD USE LITHIUM-ION BATTERY AND WHY ?

What are the Criteria for Investment and Transition to Technological and Innovative Lithium-ion Batteries?

Who should use lithium-ion batteries and why?

Lithium-ion batteries, which are considered new but have been everywhere in our lives for a long time, have become one of the most talked about and confusing topics of today with the impact of electric vehicles and the energy crisis. For the industry, the criteria for investing in and switching to lithium-ion batteries, which are more technological and innovative than lead-acid based batteries, which have been used for a long time and have not had much of an alternative until today, is a very confusing issue.

First of all, not everyone is a lithium battery customer. There is also no rule that everyone will use lithium batteries. If the application / operation can handle lead-acid batteries and the user is satisfied, there is no need to invest in lithium batteries. The golden rule is to understand the customer's needs, analyze the operation well and ask the right questions. Only after these answers can it be said whether a lithium battery is needed or not.

Below we will examine 5 questions and criteria for switching to lithium batteries;

•  Do existing lead-acid batteries last through all working shifts without any problems and require battery replacement?
•  Are lead-acid batteries intermediate charged due to the intensity of the operation?
•  Is battery maintenance a problem for the operation and is periodic maintenance performed in full?
•  Are there any violations and undesirable situations regarding safety and OHS?
•  How important is energy efficiency?
•  Is the life of lead acid batteries sufficient?

Battery Replacement / Spare Battery Problems

When using lithium batteries, there is often no need to change the battery or keep a spare battery. Lithium batteries of the same capacity offer an average of ~25% longer operating time than lead-acid batteries, thus keeping the equipment in operation longer. When this advantage is combined with the advantage of fast and intermediate charging, it allows a 3-shift operation to utilize the lost time during battery changes without the need to keep a spare battery. By eliminating or minimizing spare battery costs, you can reduce the cost items of the business. In addition, the battery charging areas and spare battery areas that become empty after the transition to lithium batteries can be used for different purposes, perhaps as a storage area. There is no need for special ventilation rooms or other requirements for charging lithium batteries.

Battery Maintenance

One of the major reasons for switching to lithium-ion batteries is battery maintenance, which is both a waste of time and a waste of money. If you don't have enough maintenance personnel on site or if operators don't complete the purge of lead-acid batteries on time, the batteries will quickly die. These maintenance are mainly;

•  Checking electrolyte levels,
•  Corrosion cleaning,
•  Addition of distilled water,
•  Periodic cell balancing,

Periodic maintenance is very important for a long and efficient use of lead-acid batteries. If the company does not have enough personnel to perform maintenance or wants to completely eliminate maintenance costs, it can provide these advantages by switching to lithium batteries.

Charging Problems with Lead Acid Batteries

Lithium batteries can reach full charge in up to 2 hours with fast charging, considering that a full charge of lead-acid batteries takes ~8 hours, charging in 2 hours means that the batteries can be filled up to 4 times faster on average.

Examining the fast charging issue in 2 different lead-acid usage scenarios will be more useful to understand whether there is a need for this advantage;

 In the first scenario, let's assume that the company has no spare battery. Lead-acid batteries are charged by leaving the vehicle to charge. The operation of cooling, charging and resting the battery after charging takes ~10 hours. This means that the vehicle stays out of operation for more than 1 shift and is not used and idle.

 In the 2nd scenario, if we assume that there is a spare battery in the enterprise, this time, the vehicles are not left in charging, but the stacker / forklift that has run out of charge goes to the exchange station for battery replacement, and most of the time it is replaced with a spare battery that is not fully charged. The disadvantage here is the cost of the spare battery, hence the increased maintenance cost... 20 minutes of battery replacement time per shift, 1 hour of wasted time per day and work accidents that may occur during battery replacement.

In an enterprise using lithium batteries, intermediate charging is done by charging the machine during meal breaks, tea breaks and every free time when there is an opportunity, without the need to buy a spare battery most of the time. By combining the advantage of fast charging, the operation continues in this way for 24 hours.

Energy Costs

Lithium batteries provide ~30% energy efficiency compared to lead-acid batteries in storing energy from the grid and converting the stored energy into work without loss (with the use of HF charger). This efficiency is directly related to the Columb efficiency of more than 99% in lithium batteries, which we have previously examined in the article on efficiency in battery systems. The equivalent of this efficiency in the field is that you can manage your operations by charging lithium batteries less than lead-acid batteries, thus paying less electricity bills. If the business has activities to increase efficiency and sustainability goals, the transition to lithium batteries will be inevitable, if not now.

OHS and Safety Concerns

The transition to lithium batteries completely avoids the following key threats and dangers;

• Acid overflow/spillage
• Overcharging / overheating
• Toxic and explosive gas-smoke
• Occupational accidents during battery replacement

In lithium batteries, the entire structure is protected by a control card called BMS. Battery and operators are under protection with overcharge / discharge, high temperature and current protections. A lithium battery made using LFP chemistry is as dangerous as a lead-acid battery. In the most unfavorable case, the cells rise to the activation temperature (250C-300C) and start to emit smoke. Since the cells do not contain oxygen due to the chemistry, there is no flame or fire risk like NMC chemistry. Water cooling is sufficient.