Typical values of voltage range from 1.2 V for a Ni/Cd battery to 3.7 V for a Li/ion battery. The following graph shows the difference between the theoretical and actual voltages for various battery systems: The discharge curve is a plot of voltage against percentage of capacity discharged.
(Recommended) Charge Current – The ideal current at which the battery is initially charged (to roughly 70 percent SOC) under constant charging scheme before transitioning into constant voltage charging. (Maximum) Internal Resistance – The resistance within the battery, generally different for charging and discharging.
A lithium-ion battery, for instance, often has a larger capacity than a lead-acid or nickel-metal hydride battery of the same size. Temperature: A battery's capacity is temperature-dependent. Higher temperatures often cause rapid aging at the price of momentary capacity increases.
The term "capacity," which is used to refer to a battery's ability to hold and distribute electrical charge, is indicated by the letter "C". It is a key variable that determines how much power a battery can deliver. The ampere-hour (Ah), which measures how much electric current a battery can produce for an hour, is the common unit of capacity.
The way the power capability is measured is in C 's. A C is the Amp-hour capacity divided by 1 hour. So the C of a 2Ah battery is 2A. The amount of current a battery 'likes' to have drawn from it is measured in C. The higher the C the more current you can draw from the battery without exhausting it prematurely.
Internal Resistance – The resistance within the battery, generally different for charging and discharging, also dependent on the battery state of charge. As internal resistance increases, the battery efficiency decreases and thermal stability is reduced as more of the charging energy is converted into heat.