What is a lithium-ion battery?
A lithium-ion battery or Li-ion battery is a type of rechargeable battery composed of cells in which lithium ions move from the negative electrode through an electrolyte to the positive electrode during discharge and back when charging.
Li-ion cells use an intercalated lithium compound as the material at the positive electrode and typically graphite at the negative electrode.
Li-ion batteries have a high energy density, no memory effect (Other than LFP cells) and low self-discharge. Cells can be manufacture to either prioritize energy or power density.
There are many ways to store energy: pumped hydroelectric storage, which stores water and later uses it to generate power; batteries that contain zinc or nickel; and molten-salt thermal storage, which generates heat, to name a few. Some of these systems can store large amounts of energy.
Lithium is a lightweight metal that an electric current can easily pass through. Lithium-ions make a battery rechargeable because their chemical reactions are reversible, allowing them to absorb power and discharge it later. Lithium-ion batteries can store a lot of energy, and they hold a charge for longer than other kinds of batteries.
While lithium-ion battery systems may have smaller storage capacity in comparison to other storage systems, they are growing in popularity because they can be installed, nearly anywhere, have a small footprint, and are inexpensive and readily available-increasing their application by utilities.
What is depth of discharge?
The DoD of a battery is the amount of the stored energy in the battery that has been used, as compared to the total capacity of the battery. Most batteries come with a recommended DoD in order to maintain the health of the battery.
What is the DoD of a lithium-ion battery?
Lithium-ion batteries are deep cycle batteries, so they have DoDs around 95%. Many lead acid batteries only have a DoD of 50%. What this means is you can use more of the energy that’s stored in a lithium-ion battery without having to charge it as often.
High energy density?
The energy density of a battery is how much power the battery can hold relative to the physical size of the battery.
Lithium-ion batteries can store more power without taking up as much space as lead acid batteries, which is great for homes where space is limited.
Lithium-ion batteries do not require maintenance like flooded lead acid batteries do.
Life span of a lithium-ion battery?
The batteries have a minimum warrantied lifespan of around 10-years, or a cycle of 10,000 cycles-whichever comes first. The batteries don’t need to be charged and recharged as often, because of the DoD.