Battery knowledge · Charging and discharging

Charger

The power electronics that convert mains or DC supply into the controlled current and voltage a battery needs. For lithium-ion it runs the CC-CV profile within the limits the BMS communicates, and stops rather than floats when the cell is full. [1]

Example

Compare charging profiles

Current holds at 5 A until the example 4.15 V threshold; voltage then holds while current tapers. The stop marker is a separate low-current termination condition.

Positive current charges the cell. Time is normalized; selected thresholds are not cell-specific recommendations. The voltage trace ends at termination; post-stop relaxation is excluded.

Explore the graph

See which quantity is held constant, when the phase changes and how charging ends.

Current profile
Current profileRelative elapsed time versus Current (A). Charge current. Interpretation follows the graphs.CCCVStop001.440.252.880.54.310.755.751Relative elapsed timeCurrent (A)
Charge current
Voltage profile
Voltage profileRelative elapsed time versus Cell voltage (V). Cell voltage. Interpretation follows the graphs.CCCVStop303.350.253.70.54.050.754.41Relative elapsed timeCell voltage (V)
Cell voltage

Current holds at 5 A until the example 4.15 V threshold; voltage then holds while current tapers. The stop marker is a separate low-current termination condition.

CC: I = I_set · CV: V = V_limit

Illustrative model. Positive current charges the cell. Time is normalized; selected thresholds are not cell-specific recommendations. The voltage trace ends at termination; post-stop relaxation is excluded.

Use in Lemonergy

Lemonergy Studio blocks

Build CC–CV charging

Native current and voltage regulation act against an explicit battery.

Blocks to use

  1. Charging schedule and target policy

    Permits charging

    Inputs & settings
    • strategy
    • targetSoc
    • departureS
    • soc, available, chargerDone → permit
  2. Regulated CC/CV charger

    Regulates current and voltage

    Inputs & settings
    • currentA
    • voltageV
    • cutoffCurrentA / cutoffHoldS
    • Electrical ports p and n
  3. Battery with SOC-dependent OCV

    Stores charge and supplies terminal voltage

    Inputs & settings
    • capacityAh
    • initialSoc
    • emptyVoltageV / fullVoltageV
    • resistanceOhm
    • Electrical ports p and n
  4. Electrical reference

    Sets zero potential

    Inputs & settings
    • Connect p to reference net

This overview identifies the components to use. Follow the example in Lemonergy for their connections and settings.

  1. Open home charging and inspect settings.
  2. Choose immediate charging; inspect mode and completion.

Example. An illustrative 100 Ah battery with a 420 V ceiling can use a 32 A cap. At the ceiling, current falls as OCV rises.

Observe. Completion needs current below cutoff at the CV ceiling for the configured dwell. Site-limited low current is different.

The battery uses linear OCV and fixed resistance. It does not automatically add aging, thermal dynamics or balancing.

Open the Studio example →

References & further reading

Technical references

  1. Lithium-ion battery fast charging: A review

    Anna Tomaszewska et al. · eTransportation · 2019

    Technical reference · CC-CV and alternative charging protocols, transport limitations, degradation and thermal implications; results depend on cell and test conditions. Software behavior is documented separately in Lemonergy block references.