Parkside 2.0 Ah 12V A3 battery X12v

Battery Protection Circuit

Battery management system BMS; battery protection circuit.

https://www.elektroda.com/qa,parkside-x20v-12v-bms-undervoltage-detect.html

• the battery pack’s BMS monitors cell voltages and signals “undervoltage” to the tool over an auxiliary pin (often marked T/DS).
• In the tool: the control PCB applies a pull‑up (e.g., ~5 V via ~10 kΩ) to that pin and measures its level. “Low” indicates OK; “float/high” indicates a fault → controller disables the PWM/drive and the tool stops
• Read the T/DS pin exactly as the tools do: provide a 10 kΩ pull‑up to 5 V and interpret ≈mid‑rail as OK and ≈5 V as fault.

https://www.reddit.com/r/Parkside/comments/1ddid9s/12v_battery_low_voltage_cutoff/

• I did a test with a Parkside 12B4 (4Ah) and it did cut off at around 8.7V which is 2.9V per cell. The battery then charges normally

20 V Battery

See https://positron96.gitlab.io/projects/parkside-battery-protection/index.html for 20V battery.

Connectors

• ID, tells the product which battery type is plugged it. Without the proper connection, the charger may overcharge, or ignore the battery

• T, Thermistor. The battery temperature; without it, the product may not accept the battery. See https://electronics.stackexchange.com/questions/10588/why-are-there-3-pins-on-some-batteries

(Reddit:) The tool supplies 5 V to the "T" pin, which, if everything is fine, the battery switches a 20 kOhm nominal NTC resistor to ground. Because the tool has a 10 kOhm resistor in series with its "T" pin the voltage drops to 3.3 V and the tool is able to detect that and start working. (https://www.reddit.com/r/batteries/comments/jwfwit/cordless_tool_battery_terminal_identification/)

See https://www.reddit.com/r/Parkside/comments/1jgixf2/parkside_batteries_wont_charge/