Laadimisspannang

Laadimisspannang, or charging voltage, is the electrical potential difference supplied to a battery or other rechargeable energy storage device during charging. It is set by the charger and is a key factor in determining charging rate, efficiency, and safety. The charging voltage is typically part of a charging protocol that also specifies the charging current and duration.

In many rechargeable cells, charging follows a constant-current, constant-voltage (CC/CV) regime. The charger provides a fixed current until the battery voltage reaches a target value, at which point the voltage is held and the current gradually decreases as the battery nears full. The exact target voltage depends on the battery chemistry and design.

Common per-cell target voltages include about 4.2 volts for lithium‑ion cells and around 3.6–3.65 volts for LiFePO4 cells. The pack voltage equals the sum of the per-cell voltages for all cells in series, with additional considerations for voltage drops in wiring and connectors. Some chemistries or charging strategies emphasize current-based termination or other indicators (such as temperature), rather than relying solely on a fixed voltage.

Measurement and control are usually performed at the battery terminals. A battery management system (BMS) may monitor voltage, temperature, and state of charge, adjusting the target charging voltage to protect safety and extend life. Tolerances exist, and excessive charging voltage can cause overheating, gas formation, or electrolyte degradation, while too low a voltage may lead to incomplete charging.

Laadimisspannang is a fundamental parameter in chargers, BMS design, and energy-storage systems, influencing both performance and longevity. See also charging profiles, cell chemistry, and safety standards for rechargeable batteries.