Lithium-Ion Battery Technology Batteries, elaborate
The chemistry of a lithium ion battery: Lithium ion batteries (often referred to as Li-ion batteries) are a rechargeable battery.
The energy is obtained when lithium ions move between an anode and a cathode.
Upon charging, the lithium ions are moved from the anode to the cathode and vice versa upon discharge.
Thus, the energy is released as the lithium ions move towards the anode. The anode is made of graphite, the cathode of cobalt oxide.
History of Li-ion Batteries:
The Li-ion battery was developed in the 1970s by M.S. Whittingham, he used an anode of metallic lithium and an anode of titanium sulfide.
Batteries with metallic lithium anodes were unsafe (they could explode) and were unsuitable for commercial use.
The first commercial Li-ion batteries were first launched by Sony in 1991 on the basis of scientific work that improved the cathodes in the Li-ion batteries and safety. Li-ion batteries are still being developed and the new one is lithium polymer batteries that will outperform the nickel batteries. The most common and widespread Li-ion batteries are based on cobalt oxide cathodes and typically hold 500-800 charges.
Pros and cons of Li-ion batteries:
Li-ion batteries are increasingly used in electronic battery-intensive devices due to the many advantages of Li-ion batteries:
Li-ion batteries have a high energy / weight ratio.
As the battery is made of the light elements Lithium (Li) and Carbon (C).
Lithium, a highly reactive element, results in a high energy / weight ratio.
A Li-ion battery contains approx. 150 watt hours (Wh) pr. kg of battery material, while an old-fashioned lead-acid battery contains only 25 Wh / kg.
A Li-ion battery is 6 times lighter than the lead acid batteries.
The amount of current in a Li-ion battery depends on the voltage of the battery (Volt, V) and its current capacity (Ampere hours, Ah).
The amount of power is given in Watt hours (Wh) and is calculated as the product of the voltage and capacity (V x A = W).
Thus, a 36-volt Li-ion battery with 10 Amp-hour capacity (10 Ah) will have power equivalent to 360 Watt hours (0.36 kWh), and the battery material will typically weigh 2.4 kg
Li-ion batteries have no memory effect.
Lack of memory effect means that you do not have to completely discharge the battery.
This is a very practical one as you can “charge” the battery without losing capacity.
If the battery is completely empty of power, it can be charged in 1 hour approx. 30%, in 2 hours, approx. 60%, a full charge takes 5 hours. After 4 hours the battery is charged 95%, not much extra charging capacity is achieved in the last hour.
See Lithium Ion charge curve above.
Li-ion batteries typically only lose 5% per month (temperature dependent) compared to a NiMH battery that loses 20% per month.
This is an advantage as the (ect) cuda 400 is not used regularly.
Li-ion batteries can hold many charges, hundreds of times without losing capacity.
Li-ion battery, ideally, can handle up to 800 charges with a capacity of at least 80%.
However, the batteries will gradually lose capacity over time, depending on the temperature at which the battery is stored.
The colder the storage the longer the shelf life.
When not using the battery, always keep it cool.
When a Li-ion battery is left on for a longer period of time, it should be half-charged (about 50-60%) and have one hour of recharging every 2 months.
This will minimize its capacity loss.
The batteries lose capacity over time – whether used or not.
When stored at 25 degrees C, capacity loss will amount to 20% per year!
If the battery is stored at even lower temperatures, the capacity loss will be reduced:
6% at 0 degrees C, while at 40 degrees C, a full 35% will be lost per year. If the battery is stored half-charged 40-60% charged, the capacity loss becomes much smaller:
2%, 4% and 15% at 0, 25 and 40 degrees C, respectively. It is an advantage not to have your battery fully charged when not in use for a period of time, and you should never have the charger permanently connected to the battery.
Overview of a Li-ion Battery’s long-lasting capacity loss for long-term storage.
Storage temperature of Li-ion battery
40% charged, Li-ion battery. vs 100% charged or discharged.
0ºC – 2% loss after 1 year vs 6% loss after 1 year
25ºC – 4% loss after 1 year vs 20% loss after 1 year
40 ºC – 15% loss after 1 year vs 35% loss after 1 year
60 ºC – 25% loss after 1 year vs 40% loss