Charging Rate (C-Rate)
Charging speeD
Wiki battery - batteries & Energy Storage
The charge and discharge rates of a battery are determined by C rates. The capacity of a battery is usually specified as 1C, which means that a fully charged battery with a capacity of 1Ah will deliver 1A for one hour.
The same battery discharged at 0.5C should deliver 0.5A for two hours, and at 2C it will deliver 2A for 30 minutes.
Losses during rapid discharges reduce the discharge time, and these losses also affect the charging times.
The same battery discharged at 0.5C should deliver 0.5A for two hours, and at 2C it will deliver 2A for 30 minutes.
![The C-rate (Charging rate/Speed) is the ratio between current and capacity [I/Ah]=[1/h] At “1 C” a battery with1.0 Ah capacity delivers 1.0 A electric current for 1 hour](https://wikibattery.org/wp-content/uploads/2022/05/C-rate-charging-rate.png)
The C-rate is derived from Coulomb’s law, which was developed by the French physicist Charles Augustin de Coulomb. The C-rate is the decisive measure for the current I with which a battery is charged or discharged.
The mAh number of a battery indicated in each case is, among other things, the 1C number. If a battery is listed as 2000 mAh, then its 1C rating is 2000 mAh.
For simplicity, the battery should provide 1C of current for one hour. In our example above, that would be 2000 mAh or 2 A of current for one hour. The same is true for a 0.5C rating. Again, the 2000 mAh battery would supply 1000 mAh or 1 A of current for two hours.
Battery capacity and the amount of energy a battery can store can be measured with a battery analyzer. The meter discharges the battery with a calibrated current, measuring the time until the final discharge voltage is reached. For Li-ion, the voltage is 3.0-4.2 V per cell.
If a 1Ah battery delivers 1A for one hour, the meter, which displays the results as a percentage of the rated output, will show 100 percent. If the discharge lasts 30 minutes before reaching the end-of-discharge voltage, the battery has a capacity of 50 percent.
A new battery is sometimes overrated and can produce more than 100 percent capacity; others are underrated and never reach 100 percent, even after discharge.
When discharging a battery with a battery meter that can apply different C rates, a higher C rate will give a lower capacity reading and vice versa. If the 1 Ah battery is discharged at the faster 2C rate, i.e., 2A, the battery should ideally deliver full capacity in 30 minutes.
The total should be the same because the same amount of energy is delivered in a shorter time. In reality, internal losses convert some energy to heat and reduce the resulting capacity to about 95 percent or less. Discharging the same battery at 0.5 C or 500 mA for 2 hours will likely increase the capacity to over 100%.
When discharging a battery with a battery meter that can apply different C rates, a higher C rate will give a lower capacity reading and vice versa. If the 1 Ah battery is discharged at the faster 2C rate, i.e., 2A, the battery should ideally deliver full capacity in 30 minutes.
The total should be the same because the same amount of energy is delivered in a shorter time. In reality, internal losses convert some energy to heat and reduce the resulting capacity to about 95 percent or less. Discharging the same battery at 0.5 C or 500 mA for 2 hours will likely increase the capacity to over 100%.
To get a good capacity value, manufacturers usually rate alkaline and lead-acid batteries at a very low 0.05C or 20 hours of discharge. Even at this slow discharge rate, lead-acid batteries rarely reach 100 percent capacity because they are overrated.
Smaller batteries are given a discharge rate of 1C. Due to the inert behavior, lead-acid is rated at 0.2C (5h) and 0.05C (20h).
While lead-acid and nickel batteries can be discharged at a high discharge rate, the protection circuitry prevents the lithium-ion power cell from discharging at more than 1C. Nickel, manganese and/or phosphate active material can tolerate discharge rates up to 10C, and the current threshold is set higher accordingly.
There are also specialty batteries that accept higher
C- rates up to 30C ! Supercapacitors (supercaps) in particular can charge and discharge quickly.
Visit also wikipedia.org
C-Rate (charging rates & discharging rates) | duration (charging speed) |
|---|---|
30 C | 2 minutes |
10 C | 6 minutes |
2 C | 30 minutes |
1 C | 1 hour |
0.5C oder C/2 | 2 hours |
0.1C oder C/10 | 10 hours |
0.05C oder C/20 | 20 hours |
Biopolymers and Bio-based Polymers WIKI BATTERY – ENERGY STORAGE & BATTERIES Startseite Biopolymers and Bio-based Polymers Introduction Biopolymers can be developed from non-fossil, bio-based feedstocks, resulting in bio-based compounds with
Stromsammler & Stromabnehmer für Lithium-Ionen AKKUS Wiki Battery – Batterien & Energiespeicher WIKI BATTERY WIKIBATTERY.ORG – BATTERIEN & ENERGIESPEICHER Aktuelle Wiki Battery Artikel Stromsammler, Stromkollektor & Stromabnehmer-Folie (Current collector) in
COBALT – GOOD OR BAD? WIKI BATTERY ENERGY STORAGE & BATTERIES WIKI BATTERY WIKI BATTERY Cobalt – A controversial battery raw material Cobalt is used in Lithium-ion batteries in large
Power density is the power per mass or volume unit.
The specific power density and the gravimetric power density are power per mass (W/kg).
The volumetric power density is power per volume (W/L)
Copper will be needed in unprecedented quantities to be used in batteries, electronics, wind and solar installations, nuclear facilities, and other things in order for the humankind to reach net-zero emissions by the year 2050.
Charging Rate (C-Rate) Charging speeD Wiki battery – batteries & Energy Storage WIKI BATTERY WIKIBATTERY.ORG – BATTERIEN & ENERGIESPEICHER What is the C-Rate? Charging Rate and Discharging Rate They are
Types of Solid-Sate Batteries WIKI BATTERY – ENERGY STORAGE & BATTERIES Solid-State Batteries with Polymer Electrolyte Solid-State Batteries with Gel Electrolyte Solid-State Batteries Introduction When it comes to next-generation energy
The energy density describes the amount of energy that can be stored in a battery per mass or per volume. There is a “volumetric energy density”, sometimes short-abbreviated as “energy density” and the specific energy density also called as the gravimetric energy density. Therefore, the amount of energy per kg (Wh/kg) or the amount of energy per litre (Wh/L).
Inorganic Solid-State Electrolytes WIKI BATTERY – ENERGY STORAGE & BATTERIES WIKI BATTERY WIKIBATTERY.ORG – BATTERIEN & ENERGIESPEICHER Inorganic Solid-State Electrolytes for Solid-State lithium Batteries Inorganic Solid-State Electrolytes Introduction The concept
Sulfur-Battery WIKI BATTERY – ENERGY STORAGE & BATTERIES WIKIBATTERY.ORG – BATTERIES & ENERGY STORAGE WIKIBATTERY.ORG – BATTERIES & ENERGY STORAGE Sulfur-Battery Name The sulfur-battery is often referred to the lithium-sulfur
Lithium nickel manganese cobalt (NMC 811 or NCM) WIKI BATTERY ENERGY STORAGE & BATTERIES WIKI BATTERY WIKI BATTERY Lese diesen Artikel auf Deutsch Lithium nickel manganese cobalt (NMC 811 or
International Energy Agency IEA Wiki Battery – Batterien & Energiespeicher WIKI BATTERY WIKIBATTERY.ORG – BATTERIEN & ENERGIESPEICHER Die Internationale Energieagentur IEA vorgestellt Die Internationale Energieagentur – IEA Internationale Energieagentur IEA
WIKIBATTERY.ORG
Wiki Battery is an encyclopedia for battery technologies, which explains technical terms from the field of batteries and energy storage in a simple and understandable way – dummy proof.
More information about Wiki Battery can be found here. Wiki Battery is a published Swiss Battery (SwissBattery.com).
All rights reserved.
Copyright © 2023-2030 by WikiBattery.org
Contact - Get in touch with us
Newsletter
Want updates on everything we do? Sign up for the quarterly newsletter.
