APPARATUS TO DETECT DEFECTIVE BATTERY MODULE AND ABNORMALITY IN A SEQUENTIAL CHARGING CONTROL CHAIN
The charging and/or discharging of a set of swappable battery modules in a battery system is carried out automatically using a set of charging and/or discharging control switches linked in a sequential charging and/or a discharging control chain. The charging and discharging of the set of battery modules can be done sequentially or in parallel, and is hardware-based with minimal software/firmware involvement. The system is scalable and automatically reconfigurable for use in an infrastructure and/or in an electric vehicle. The swappable battery modules may be positioned in the battery slots or butted together in the battery system.
1 - 50 . (canceled)
51 . A circuit adapted to detect a defective battery module in a battery slot controlled by a control switch of a sequential charging control chain, the circuit comprising:
a timer including a down-counter and a counter enable logic; and
a Set/Reset Flip-Flop (SRFF), wherein
when the battery module is in the battery slot, a signal adapted to detect a presence of the battery module in the battery slot is asserted; and
at assertion of a charging input enable signal applied to the control switch without a charging-enable output signal being asserted by the control switch to a succeeding control switch in the sequential charging control chain, a pre-set value is loaded into the down-counter and causes the down-counter to decrement in response to each pulse of a clock signal, wherein
when the down-counter is decremented to a zero count, the SRFF is set and the battery module is detected as defective; and
when the control switch asserts the charging-enable output signal before the down-counter is decremented to the zero count, the battery module is not detected as being defective.
52 . The circuit of claim 51 , wherein a normally-closed direct contact limit switch is adapted to detect the presence of the battery module in the battery slot, and wherein:
when the battery module is not in the battery slot, the direct contact limit switch is closed and outputs a high value to inhibit the control switch; and
when the battery module is in the battery slot, the direct limit contact switch is open, and output of the direct contact limit switch is pulled to a low value by a pull-down resistor.
53 . The circuit of claim 51 , wherein the counter enable logic is a logical AND of:
a signal adapted to detect the presence of the battery module in the battery slot;
the charging enable input signal being asserted by the control switch; and
a signal adapted to detect a status of the down-counter.
54 . The circuit of claim 53 , wherein the status of the down-counter is detectable from an output of the SRFF and the charging-enable output signal to the succeeding control switch, wherein
when the down-counter is decremented to zero count and the battery module is not fully charged, the SRFF is set to inhibit the control switch and to assert the charging-enable output signal, and
when the down-counter is not decremented to zero count, assertion of the charging-enable output signal indicates the battery module is fully charged while the SRFF is not set.
55 . The circuit of claim 51 , wherein
an output of the SRFF is observable as a defective battery module indicator, and the pre-set value loaded into the down-counter is programmable.
56 . The circuit of claim 51 , wherein when the battery module is removed from the battery slot, the SRFF is reset.
57 . A circuit adapted to detect a defective battery module in a battery slot controlled by a control switch of a sequential charging control chain, the circuit comprising:
a timer including an up-counter, a comparator, and a counter enable logic; and
a Set/Reset Flip-Flop (SRFF); wherein
when the battery module is in the battery slot, a signal adapted to indicate presence of the battery module battery slot is asserted; and
at assertion of a charging input enable signal applied to the control switch without asserting a charging-enable output signal to a succeeding control switch in the sequential charging control chain, the up-counter is enabled to increment in response to each pulse of a clock signal, wherein
when the up-counter is incremented to reach a pre-set value being monitored by the comparator, the SRFF is set and the battery module is detected as being defective; and
when the control switch asserts the charging-enable output signal before the up-counter's count reaches the pre-set value, the battery module is detected as not being defective.
58 . The circuit of claim 57 , wherein the counter enable logic is a logical AND of:
a signal to detect presence of the battery module in the battery slot;
the charging enable input signal being asserted by the control switch; and
a signal adapted to detect a status of the up-counter.
59 . The circuit of claim 58 , wherein the status of the up-counter is detectable from an output of the SRFF and the charging-enable output signal to the succeeding control switch, wherein
when the up-counter is incremented to the pre-set value and the battery module is not fully charged, the SRFF is set to inhibit the control switch and to assert the charging-enable output signal, and
when the up-counter is not incremented to reach the pre-set value, assertion of the charging-enable output signal indicates the battery module is fully charged while the SRFF is not set.
60 . The circuit of claim 57 , wherein an output of the SRFF is observable as a defective battery module indicator, and the pre-set value is programmable.
61 . The circuit of claim 57 , wherein an energy status of the battery module is observable from a status output port coupled to output of a comparator disposed in the control switch, wherein the comparator is adapted to compare an attenuated voltage from the battery module with a reference voltage.
62 . The circuit of claim 57 , wherein the up-counter is cleared by one of:
an external reset;
removing the battery module from the battery slot; and
assertion of the charging enabling output signal to the succeeding control switch.
63 . A circuit adapted to detect abnormality in a charging control switch coupled to a battery module in a battery slot, the circuit comprises a logical AND function of following inputs:
(i) inversion of an output of a direct contact switch coupled to the battery slot indicting presence of the battery module in the battery slot;
(ii) inversion of an energy status of the battery module monitored by a comparator disposed in the charging control switch, wherein when an abnormal event takes place, the battery module charging terminates and the comparator is saturated to a logic low when an attenuated energy derived from the battery module and monitored by the comparator is below a reference voltage;
(iii) inversion of an output of a detection circuit adapted to detect a defect in the battery module to indicate no defect is being detected; and
(iv) assertion of a charging-enable output signal from the charging control switch which indicates battery charging process is terminated.
64 . The circuit of claim 63 wherein the circuit is adapted to detect one or more abnormalities in the charging control switch, wherein the one or more abnormalities include at least one of over-temperature, over-current, short circuit, or over-voltage of external power input.