A battery pack (10) is connected to a load or charger (12) and includes battery cells (20), under-voltage switch (22), a first voltage controlled switch (24), over-voltage switch (28), and second voltage controlled switch (30). Under-voltage switch (22) can block only discharge current, any recharge current may pass through it regardless of its switch state. Over-voltage switch (28) can block only recharge current when switched off and will always allow discharge current to flow regardless of its switch state. First voltage controlled switch (24) maintains under-voltage switch (22) on while battery voltage V1 is above a predetermined under-voltage level. When V1 drops to, or below, the under-voltage level first voltage controlled switch (24) switches off under-voltage switch (22) with a switch signal on line (26). Second voltage controlled switch (30) maintains over-voltage switch (28) on while battery voltage V1 is below a predetermined over-voltage level. When V1 reaches or exceeds the over-voltage level second voltage controlled switch turns off over-voltage switch (28) via a switch signal on line (34).
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