A low-voltage cutout shall be provided to disconnect the battery when it is fully discharged.
At full-charge situation, the battery will be protected by over-charge protection circuitry.
Battery
Sealed Ni-Cad 100% Rechargeable Battery Pack
Outside Features
“Test” button, "Red” charging indicator, “Green” power indicator
Test Standards
EN60598-2-22. BS5266-2 PPA104A (4th Revision) of FSD