Apparatuses and methods for removing defective energy storage cells from an energy storage array
Apparatuses and methods for removing a defective energy storage cell from an energy storage array is described. An apparatus includes an energy storage array including a plurality of energy storage cells, and a cell removal circuit coupled to the energy storage array. The cell removal circuit is configured to prevent a defective energy storage cell of the plurality of energy storage cells from causing other energy storage cells of the plurality of energy storage cells to become defective. A method includes receiving power at a charging node of an energy storage array, the energy storage array including a plurality of energy storage cells. Responsive to failure of an energy storage cell of the plurality of energy storage cells, current is provided through the defective energy storage cell, and responsive to the defective energy storage cell becoming an open circuit, discontinuing provision of the current through the defective energy storage cell.
1. A method, comprising:
receiving a charging voltage at a first plurality of energy storage cells of a first row of an energy storage array;
propagating a portion of the charging voltage to a second plurality of energy storage cells of a second row of the energy storage array from the first row;
responsive to failure of an energy storage cell of the first plurality of energy storage cells of the first row, providing current through the defective energy storage cell to a reference node, wherein providing current through the defective energy storage cell to a reference node comprises:
reverse-biasing a zener diode coupled in parallel with the second plurality of energy storage cells of the second row of the energy storage array;
providing current through the defective energy storage device to a reference node via the reverse-biased zener diode; and
providing current through the defective energy storage device via a buffer of the cell removal circuit; and
responsive to the defective energy storage cell becoming an open circuit, discontinuing provision of the current through the defective energy storage cell, wherein discontinuing provision of the current through the defective energy storage cell comprises forward-biasing the zener diode responsive to the defective energy storage cell becoming an open circuit.
2. The method of claim 1 , wherein the current is based on the charging voltage.
3. The method of claim 1 , further comprising:
detecting failure of the energy storage cell at a buffer of the cell removal circuit; and
responsive to detecting failure of the energy storage cell, providing current to the defective energy storage cell via the buffer.
4. The method of claim 1 , further comprising blowing a sacrificial component of the defective energy storage cell responsive to the current to cause the defective energy storage cell to become an open circuit.
5. The method of claim 1 , wherein block the sacrificial component of the defective energy storage cell comprises blowing a fuse.