hitl_tester.test_cases.bms.test_402t

Modified version of the tests in test_2590_cell_sims.py, for testing 402T testing.

Used in these test plans:

402t_1_3 ⠀⠀⠀(bms/402t_1_3.plan)
402t_1_4 ⠀⠀⠀(bms/402t_1_4.plan)
402t_2_1 ⠀⠀⠀(bms/402t_2_1.plan)
402t ⠀⠀⠀(bms/402t.plan)

Example Command (warning: test plan may run other test cases):

./hitl_tester.py 402t_1_3 -DCHARGE_VOLTAGE=16 -DCHARGE_TIME=86400 -DCHARGE_CURRENT=0.18 -DSAMPLE_INTERVAL=10 -DDEFAULT_SCAN_INDEX=18 -DSTEP_START=1 -DSTEP_END=7 -DREST_TIME=0 -DOLD_CURRENTS=False

View Source

  1"""
  2Modified version of the tests in test_2590_cell_sims.py, for testing 402T testing.
  3"""
  4
  5from __future__ import annotations
  6
  7import time
  8from contextlib import suppress
  9
 10import pytest
 11
 12from hitl_tester.modules.bms.bms_hw import BMSHardware
 13from hitl_tester.modules.bms.plateset import Plateset
 14from hitl_tester.modules.bms_types import DischargeType, TimeoutExceededError
 15from hitl_tester.modules.logger import logger
 16
 17CHARGE_VOLTAGE = 16
 18CHARGE_TIME = 24 * 3600  # 24 hours
 19CHARGE_CURRENT = 0.180
 20SAMPLE_INTERVAL = 10
 21DEFAULT_SCAN_INDEX = 18
 22STEP_START = 1
 23STEP_END = 7
 24REST_TIME = 0
 25OLD_CURRENTS = False
 26
 27bms_hardware = BMSHardware(pytest.flags)  # type: ignore[arg-type]
 28bms_hardware.init()
 29
 30plateset = Plateset()
 31
 32
 33# FIXME(JA): docs, refactor
 34
 35
 36def standard_charge(
 37    charge_current: float = 2,
 38    max_time: int = 7 * 24 * 3600,
 39    sample_interval: int = 10,
 40    minimum_readings: int = 3,
 41    charge_voltage: float = 16.8,
 42    termination_current: float = 0.100,
 43):
 44    """
 45    Charge batteries in accordance with 4.3.1 for not greater than three hours.
 46    4.3.1 = 23 ± 5°C (73.4°F) ambient pressure/relative humidity, with 2+ hours between charge and discharge.
 47    """
 48    bms_hardware.voltage = charge_voltage
 49    bms_hardware.ov_protection = bms_hardware.voltage + 0.050  # 50mV above the charging voltage
 50    bms_hardware.current = charge_current
 51    bms_hardware.termination_current = termination_current
 52    bms_hardware.max_time = max_time
 53    bms_hardware.sample_interval = sample_interval
 54    bms_hardware.minimum_readings = minimum_readings
 55
 56    # Run the Charge cycle
 57    bms_hardware.run_li_charge_cycle()
 58
 59
 60def standard_discharge(
 61    discharge_current: float = 2,
 62    max_time: int = 7 * 24 * 3600,
 63    sample_interval: int = 10,
 64    discharge_voltage: float = 10,
 65):
 66    """Discharge at 2A until 10V."""
 67    bms_hardware.voltage = discharge_voltage
 68    bms_hardware.uv_protection = -0.05  # bms_hardware.voltage - 0.050  # 50mV below voltage cutoff
 69    bms_hardware.current = discharge_current
 70    bms_hardware.discharge_type = DischargeType.CONSTANT_CURRENT
 71    bms_hardware.max_time = max_time
 72    bms_hardware.sample_interval = sample_interval
 73
 74    # Run the discharge cycle, returning the capacity
 75    capacity = bms_hardware.run_discharge_cycle()
 76    logger.write_info_to_report(f"Discharge complete, capacity was {capacity * 1000.0} mAh")
 77    return capacity
 78
 79
 80def log_dmm_data():
 81    """Log all DMM data."""
 82    for i, name in enumerate(
 83        [
 84            "Cell 1",
 85            "Cell 2",
 86            "Cell 3",
 87            "Cell 4",
 88            "Cell 5",
 89            "Cell 6",
 90            "Cell 7",
 91            "Cell 8",
 92            "Cell 9",
 93            "Cell 10",
 94            "Thermistor 2",
 95            "Thermistor 1",
 96            "BT (Battery Terminal)",
 97            "Charge",
 98        ]
 99    ):
100        bms_hardware.dmm.scan_index = i
101        logger.write_info_to_report(f"{name} = {bms_hardware.dmm.volts} V")
102    bms_hardware.dmm.scan_index = DEFAULT_SCAN_INDEX
103
104
105@pytest.mark.skipif(STEP_END < 1 or STEP_START > 1, reason=f"Starting on step {STEP_START}")
106def test_step_1_402t():
107    """
108    Discharge at 104 mA down to 9V
109    """
110    standard_discharge(sample_interval=SAMPLE_INTERVAL, discharge_current=0.104, discharge_voltage=9)
111
112
113@pytest.mark.skipif(STEP_END < 2 or STEP_START > 2, reason=f"Starting on step {STEP_START}")
114def test_step_2_402t():
115    """
116    Charge 250 mA, 50400 seconds
117    """
118    with suppress(TimeoutExceededError):
119        standard_charge(
120            sample_interval=SAMPLE_INTERVAL,
121            charge_current=CHARGE_CURRENT,
122            termination_current=-0.05,
123            charge_voltage=CHARGE_VOLTAGE,
124            max_time=50400,
125        )
126
127
128@pytest.mark.skipif(STEP_END < 3 or STEP_START > 3, reason=f"Starting on step {STEP_START}")
129def test_step_3_402t():
130    """
131    Discharge at 104 mA down to 9V
132    """
133    standard_discharge(sample_interval=SAMPLE_INTERVAL, discharge_current=0.104, discharge_voltage=9)
134
135
136@pytest.mark.skipif(STEP_END < 4 or STEP_START > 4, reason=f"Starting on step {STEP_START}")
137def test_step_4_402t():
138    """
139    Charge 250 mA, 50400 seconds
140    """
141    with suppress(TimeoutExceededError):
142        standard_charge(
143            sample_interval=SAMPLE_INTERVAL,
144            charge_current=CHARGE_CURRENT,
145            termination_current=-0.05,
146            charge_voltage=CHARGE_VOLTAGE,
147            max_time=50400,
148        )
149
150
151@pytest.mark.skipif(STEP_END < 5 or STEP_START > 5, reason=f"Starting on step {STEP_START}")
152def test_step_5_402t():
153    """
154    Discharge at 104 / 180 mA down to 9V
155    """
156    standard_discharge(
157        sample_interval=SAMPLE_INTERVAL, discharge_current=0.104 if OLD_CURRENTS else 0.180, discharge_voltage=9
158    )
159
160
161@pytest.mark.skipif(STEP_END < 6 or STEP_START > 6, reason=f"Starting on step {STEP_START}")
162def test_step_6_402t():
163    """
164    Charge at 180 / 120 mA for 50400 seconds
165    Let pack rest for at least 5 hours
166    Discharge at 180 / 120 mA down to 10V (save data)
167    """
168    with suppress(TimeoutExceededError):
169        standard_charge(
170            sample_interval=SAMPLE_INTERVAL,
171            charge_current=CHARGE_CURRENT if OLD_CURRENTS else 0.120,
172            termination_current=-0.05,
173            charge_voltage=CHARGE_VOLTAGE,
174            max_time=CHARGE_TIME,
175        )
176    standard_discharge(sample_interval=SAMPLE_INTERVAL, discharge_current=0.120, discharge_voltage=10)
177
178
179@pytest.mark.skipif(STEP_END < 7 or STEP_START > 7, reason=f"Starting on step {STEP_START}")
180def test_step_7_402t():
181    """
182    Charge at 250 mA for 50400 seconds
183    Let pack rest for at least 5 hours
184    """
185    with suppress(TimeoutExceededError):
186        standard_charge(
187            sample_interval=SAMPLE_INTERVAL,
188            charge_current=CHARGE_CURRENT if OLD_CURRENTS else 0.120,
189            termination_current=-0.05,
190            charge_voltage=CHARGE_VOLTAGE,
191            max_time=CHARGE_TIME,
192        )
193    bms_hardware.max_time = 48 * 3600
194    bms_hardware.sample_interval = SAMPLE_INTERVAL
195    bms_hardware.run_resting_cycle()
196
197    # Measure impedance
198    pulse_current = 1.0
199    raw_voltage_data = bms_hardware.csv.ocv.measure_impedance_data(pulse_current)
200    impedance = bms_hardware.csv.ocv.calculate_impedance(raw_voltage_data, pulse_current)
201    bms_hardware.csv.raw_impedance.record(impedance, raw_voltage_data)
202    logger.write_result_to_html_report(f"Impedance: {impedance} mΩ")
203
204
205@pytest.mark.skipif(STEP_END < 10 or STEP_START > 10, reason=f"Starting on step {STEP_START}")
206def test_step_10_402t():
207    """
208    A: Discharge the pack at 100 mA for 15 minutes
209    B: Discharge the pack at 230 mA for 5 minutes
210    C: Discharge the pack at a base rate of 340 mA for 5 minutes. While discharging, pulse (increase) the current
211       discharge by an additional 1.5 A (1500 mA). The pulses will happen throughout the discharge, starting at a
212       frequency of 400 Hz and increasing linearly up to 1000 Hz by the end of the 5 minute test.
213    D: Rest for 5 minutes. We need to see the open circuit voltage be above 12.5V.
214    """
215    with suppress(TimeoutExceededError):
216        standard_discharge(
217            sample_interval=SAMPLE_INTERVAL, discharge_current=0.100, discharge_voltage=9, max_time=15 * 60
218        )
219    with suppress(TimeoutExceededError):
220        standard_discharge(
221            sample_interval=SAMPLE_INTERVAL, discharge_current=0.230, discharge_voltage=9, max_time=5 * 60
222        )
223
224    bms_hardware.load.configure_frequency_trigger()
225    bms_hardware.load.enable()
226    # bms_hardware.load.transient_mode(True)
227    bms_hardware.load.send_trigger()
228    start_time = time.perf_counter()
229    while (runtime := time.perf_counter() - start_time) < 5 * 60:
230        # Increase frequency
231        progress = runtime / (5 * 60)
232        bms_hardware.load.change_frequency(frequency := 0.4 + 0.6 * progress)
233
234        # Log rest data
235        current = -1 * bms_hardware.load.amps
236        logger.write_info_to_report(
237            f"Elapsed Time: {runtime:.1f}, Voltage: {bms_hardware.dmm.volts}, Current: {current}, "
238            f"Frequency: {frequency}"
239        )
240        bms_hardware.csv.cycle.record(runtime, current)
241
242        time.sleep(1)
243    # bms_hardware.load.transient_mode(False)
244    bms_hardware.load.disable()
245
246    # Rest for 5 minutes (12.5V+)
247    bms_hardware.max_time = 5.25 * 60
248    bms_hardware.sample_interval = SAMPLE_INTERVAL
249    bms_hardware.run_resting_cycle()
250
251
252@pytest.mark.skipif(STEP_END < 11 or STEP_START > 11, reason=f"Starting on step {STEP_START}")
253def test_step_11_402t():
254    """
255    1. Measure open circuit voltage
256    2. Temp Cycle in thermal chamber per MIL-STD-202, method 102 (now 107), letter D:
257    - Bring pack to -40C (+0, -5) for 1 hour
258    - Bring pack to 25C (+10, -5) for no more than 5 minutes
259    - Bring pack to 60C (+5, -0) for 1 hour
260    - Bring pack to 25C (+10, -5) for no more than 5 minutes
261    - Repeat preceding 4 steps 5 times
262    3. Inspect for any physical/mechanical defects
263    4. Measure open circuit voltage
264    """
265    bms_hardware.sample_interval = SAMPLE_INTERVAL
266    bms_hardware.thermal_chamber.internal_units = "C"
267    for i in range(5):
268        logger.write_info_to_report(f"Step 11.{i}")
269        bms_hardware.thermal_chamber.set_point_temperature = -40
270        bms_hardware.max_time = 3600
271        bms_hardware.run_resting_cycle()
272        bms_hardware.thermal_chamber.set_point_temperature = 25
273        bms_hardware.max_time = 5 * 60
274        bms_hardware.run_resting_cycle()
275        bms_hardware.thermal_chamber.set_point_temperature = 60
276        bms_hardware.max_time = 3600
277        bms_hardware.run_resting_cycle()
278        bms_hardware.thermal_chamber.set_point_temperature = 25
279        bms_hardware.max_time = 5 * 60
280        bms_hardware.run_resting_cycle()
281
282
283@pytest.mark.skipif(REST_TIME == 0, reason="Resting not requested")
284def test_resting():
285    """Record resting data."""
286    bms_hardware.max_time = REST_TIME
287    bms_hardware.sample_interval = SAMPLE_INTERVAL
288    bms_hardware.run_resting_cycle()

CHARGE_VOLTAGE = 16

CHARGE_TIME = 86400

CHARGE_CURRENT = 0.18

SAMPLE_INTERVAL = 10

DEFAULT_SCAN_INDEX = 18

STEP_START = 1

STEP_END = 7

REST_TIME = 0

OLD_CURRENTS = False

bms_hardware = <hitl_tester.modules.bms.bms_hw.BMSHardware object>

plateset = <hitl_tester.modules.bms.plateset.Plateset object>

def standard_charge( charge_current: float = 2, max_time: int = 604800, sample_interval: int = 10, minimum_readings: int = 3, charge_voltage: float = 16.8, termination_current: float = 0.1): View Source

37def standard_charge(
38    charge_current: float = 2,
39    max_time: int = 7 * 24 * 3600,
40    sample_interval: int = 10,
41    minimum_readings: int = 3,
42    charge_voltage: float = 16.8,
43    termination_current: float = 0.100,
44):
45    """
46    Charge batteries in accordance with 4.3.1 for not greater than three hours.
47    4.3.1 = 23 ± 5°C (73.4°F) ambient pressure/relative humidity, with 2+ hours between charge and discharge.
48    """
49    bms_hardware.voltage = charge_voltage
50    bms_hardware.ov_protection = bms_hardware.voltage + 0.050  # 50mV above the charging voltage
51    bms_hardware.current = charge_current
52    bms_hardware.termination_current = termination_current
53    bms_hardware.max_time = max_time
54    bms_hardware.sample_interval = sample_interval
55    bms_hardware.minimum_readings = minimum_readings
56
57    # Run the Charge cycle
58    bms_hardware.run_li_charge_cycle()

Charge batteries in accordance with 4.3.1 for not greater than three hours. 4.3.1 = 23 ± 5°C (73.4°F) ambient pressure/relative humidity, with 2+ hours between charge and discharge.

def standard_discharge( discharge_current: float = 2, max_time: int = 604800, sample_interval: int = 10, discharge_voltage: float = 10): View Source

61def standard_discharge(
62    discharge_current: float = 2,
63    max_time: int = 7 * 24 * 3600,
64    sample_interval: int = 10,
65    discharge_voltage: float = 10,
66):
67    """Discharge at 2A until 10V."""
68    bms_hardware.voltage = discharge_voltage
69    bms_hardware.uv_protection = -0.05  # bms_hardware.voltage - 0.050  # 50mV below voltage cutoff
70    bms_hardware.current = discharge_current
71    bms_hardware.discharge_type = DischargeType.CONSTANT_CURRENT
72    bms_hardware.max_time = max_time
73    bms_hardware.sample_interval = sample_interval
74
75    # Run the discharge cycle, returning the capacity
76    capacity = bms_hardware.run_discharge_cycle()
77    logger.write_info_to_report(f"Discharge complete, capacity was {capacity * 1000.0} mAh")
78    return capacity

Discharge at 2A until 10V.

def log_dmm_data(): View Source

 81def log_dmm_data():
 82    """Log all DMM data."""
 83    for i, name in enumerate(
 84        [
 85            "Cell 1",
 86            "Cell 2",
 87            "Cell 3",
 88            "Cell 4",
 89            "Cell 5",
 90            "Cell 6",
 91            "Cell 7",
 92            "Cell 8",
 93            "Cell 9",
 94            "Cell 10",
 95            "Thermistor 2",
 96            "Thermistor 1",
 97            "BT (Battery Terminal)",
 98            "Charge",
 99        ]
100    ):
101        bms_hardware.dmm.scan_index = i
102        logger.write_info_to_report(f"{name} = {bms_hardware.dmm.volts} V")
103    bms_hardware.dmm.scan_index = DEFAULT_SCAN_INDEX

Log all DMM data.

@pytest.mark.skipif(STEP_END < 1 or STEP_START > 1, reason=f'Starting on step {STEP_START}')

def test_step_1_402t(): View Source

106@pytest.mark.skipif(STEP_END < 1 or STEP_START > 1, reason=f"Starting on step {STEP_START}")
107def test_step_1_402t():
108    """
109    Discharge at 104 mA down to 9V
110    """
111    standard_discharge(sample_interval=SAMPLE_INTERVAL, discharge_current=0.104, discharge_voltage=9)

Discharge at 104 mA down to 9V

@pytest.mark.skipif(STEP_END < 2 or STEP_START > 2, reason=f'Starting on step {STEP_START}')

def test_step_2_402t(): View Source

114@pytest.mark.skipif(STEP_END < 2 or STEP_START > 2, reason=f"Starting on step {STEP_START}")
115def test_step_2_402t():
116    """
117    Charge 250 mA, 50400 seconds
118    """
119    with suppress(TimeoutExceededError):
120        standard_charge(
121            sample_interval=SAMPLE_INTERVAL,
122            charge_current=CHARGE_CURRENT,
123            termination_current=-0.05,
124            charge_voltage=CHARGE_VOLTAGE,
125            max_time=50400,
126        )

Charge 250 mA, 50400 seconds

@pytest.mark.skipif(STEP_END < 3 or STEP_START > 3, reason=f'Starting on step {STEP_START}')

def test_step_3_402t(): View Source

129@pytest.mark.skipif(STEP_END < 3 or STEP_START > 3, reason=f"Starting on step {STEP_START}")
130def test_step_3_402t():
131    """
132    Discharge at 104 mA down to 9V
133    """
134    standard_discharge(sample_interval=SAMPLE_INTERVAL, discharge_current=0.104, discharge_voltage=9)

Discharge at 104 mA down to 9V

@pytest.mark.skipif(STEP_END < 4 or STEP_START > 4, reason=f'Starting on step {STEP_START}')

def test_step_4_402t(): View Source

137@pytest.mark.skipif(STEP_END < 4 or STEP_START > 4, reason=f"Starting on step {STEP_START}")
138def test_step_4_402t():
139    """
140    Charge 250 mA, 50400 seconds
141    """
142    with suppress(TimeoutExceededError):
143        standard_charge(
144            sample_interval=SAMPLE_INTERVAL,
145            charge_current=CHARGE_CURRENT,
146            termination_current=-0.05,
147            charge_voltage=CHARGE_VOLTAGE,
148            max_time=50400,
149        )

Charge 250 mA, 50400 seconds

@pytest.mark.skipif(STEP_END < 5 or STEP_START > 5, reason=f'Starting on step {STEP_START}')

def test_step_5_402t(): View Source

152@pytest.mark.skipif(STEP_END < 5 or STEP_START > 5, reason=f"Starting on step {STEP_START}")
153def test_step_5_402t():
154    """
155    Discharge at 104 / 180 mA down to 9V
156    """
157    standard_discharge(
158        sample_interval=SAMPLE_INTERVAL, discharge_current=0.104 if OLD_CURRENTS else 0.180, discharge_voltage=9
159    )

Discharge at 104 / 180 mA down to 9V

@pytest.mark.skipif(STEP_END < 6 or STEP_START > 6, reason=f'Starting on step {STEP_START}')

def test_step_6_402t(): View Source

162@pytest.mark.skipif(STEP_END < 6 or STEP_START > 6, reason=f"Starting on step {STEP_START}")
163def test_step_6_402t():
164    """
165    Charge at 180 / 120 mA for 50400 seconds
166    Let pack rest for at least 5 hours
167    Discharge at 180 / 120 mA down to 10V (save data)
168    """
169    with suppress(TimeoutExceededError):
170        standard_charge(
171            sample_interval=SAMPLE_INTERVAL,
172            charge_current=CHARGE_CURRENT if OLD_CURRENTS else 0.120,
173            termination_current=-0.05,
174            charge_voltage=CHARGE_VOLTAGE,
175            max_time=CHARGE_TIME,
176        )
177    standard_discharge(sample_interval=SAMPLE_INTERVAL, discharge_current=0.120, discharge_voltage=10)

Charge at 180 / 120 mA for 50400 seconds Let pack rest for at least 5 hours Discharge at 180 / 120 mA down to 10V (save data)

@pytest.mark.skipif(STEP_END < 7 or STEP_START > 7, reason=f'Starting on step {STEP_START}')

def test_step_7_402t(): View Source

180@pytest.mark.skipif(STEP_END < 7 or STEP_START > 7, reason=f"Starting on step {STEP_START}")
181def test_step_7_402t():
182    """
183    Charge at 250 mA for 50400 seconds
184    Let pack rest for at least 5 hours
185    """
186    with suppress(TimeoutExceededError):
187        standard_charge(
188            sample_interval=SAMPLE_INTERVAL,
189            charge_current=CHARGE_CURRENT if OLD_CURRENTS else 0.120,
190            termination_current=-0.05,
191            charge_voltage=CHARGE_VOLTAGE,
192            max_time=CHARGE_TIME,
193        )
194    bms_hardware.max_time = 48 * 3600
195    bms_hardware.sample_interval = SAMPLE_INTERVAL
196    bms_hardware.run_resting_cycle()
197
198    # Measure impedance
199    pulse_current = 1.0
200    raw_voltage_data = bms_hardware.csv.ocv.measure_impedance_data(pulse_current)
201    impedance = bms_hardware.csv.ocv.calculate_impedance(raw_voltage_data, pulse_current)
202    bms_hardware.csv.raw_impedance.record(impedance, raw_voltage_data)
203    logger.write_result_to_html_report(f"Impedance: {impedance} mΩ")

Charge at 250 mA for 50400 seconds Let pack rest for at least 5 hours

@pytest.mark.skipif(STEP_END < 10 or STEP_START > 10, reason=f'Starting on step {STEP_START}')

def test_step_10_402t(): View Source

206@pytest.mark.skipif(STEP_END < 10 or STEP_START > 10, reason=f"Starting on step {STEP_START}")
207def test_step_10_402t():
208    """
209    A: Discharge the pack at 100 mA for 15 minutes
210    B: Discharge the pack at 230 mA for 5 minutes
211    C: Discharge the pack at a base rate of 340 mA for 5 minutes. While discharging, pulse (increase) the current
212       discharge by an additional 1.5 A (1500 mA). The pulses will happen throughout the discharge, starting at a
213       frequency of 400 Hz and increasing linearly up to 1000 Hz by the end of the 5 minute test.
214    D: Rest for 5 minutes. We need to see the open circuit voltage be above 12.5V.
215    """
216    with suppress(TimeoutExceededError):
217        standard_discharge(
218            sample_interval=SAMPLE_INTERVAL, discharge_current=0.100, discharge_voltage=9, max_time=15 * 60
219        )
220    with suppress(TimeoutExceededError):
221        standard_discharge(
222            sample_interval=SAMPLE_INTERVAL, discharge_current=0.230, discharge_voltage=9, max_time=5 * 60
223        )
224
225    bms_hardware.load.configure_frequency_trigger()
226    bms_hardware.load.enable()
227    # bms_hardware.load.transient_mode(True)
228    bms_hardware.load.send_trigger()
229    start_time = time.perf_counter()
230    while (runtime := time.perf_counter() - start_time) < 5 * 60:
231        # Increase frequency
232        progress = runtime / (5 * 60)
233        bms_hardware.load.change_frequency(frequency := 0.4 + 0.6 * progress)
234
235        # Log rest data
236        current = -1 * bms_hardware.load.amps
237        logger.write_info_to_report(
238            f"Elapsed Time: {runtime:.1f}, Voltage: {bms_hardware.dmm.volts}, Current: {current}, "
239            f"Frequency: {frequency}"
240        )
241        bms_hardware.csv.cycle.record(runtime, current)
242
243        time.sleep(1)
244    # bms_hardware.load.transient_mode(False)
245    bms_hardware.load.disable()
246
247    # Rest for 5 minutes (12.5V+)
248    bms_hardware.max_time = 5.25 * 60
249    bms_hardware.sample_interval = SAMPLE_INTERVAL
250    bms_hardware.run_resting_cycle()

A: Discharge the pack at 100 mA for 15 minutes B: Discharge the pack at 230 mA for 5 minutes C: Discharge the pack at a base rate of 340 mA for 5 minutes. While discharging, pulse (increase) the current discharge by an additional 1.5 A (1500 mA). The pulses will happen throughout the discharge, starting at a frequency of 400 Hz and increasing linearly up to 1000 Hz by the end of the 5 minute test. D: Rest for 5 minutes. We need to see the open circuit voltage be above 12.5V.

@pytest.mark.skipif(STEP_END < 11 or STEP_START > 11, reason=f'Starting on step {STEP_START}')

def test_step_11_402t(): View Source

253@pytest.mark.skipif(STEP_END < 11 or STEP_START > 11, reason=f"Starting on step {STEP_START}")
254def test_step_11_402t():
255    """
256    1. Measure open circuit voltage
257    2. Temp Cycle in thermal chamber per MIL-STD-202, method 102 (now 107), letter D:
258    - Bring pack to -40C (+0, -5) for 1 hour
259    - Bring pack to 25C (+10, -5) for no more than 5 minutes
260    - Bring pack to 60C (+5, -0) for 1 hour
261    - Bring pack to 25C (+10, -5) for no more than 5 minutes
262    - Repeat preceding 4 steps 5 times
263    3. Inspect for any physical/mechanical defects
264    4. Measure open circuit voltage
265    """
266    bms_hardware.sample_interval = SAMPLE_INTERVAL
267    bms_hardware.thermal_chamber.internal_units = "C"
268    for i in range(5):
269        logger.write_info_to_report(f"Step 11.{i}")
270        bms_hardware.thermal_chamber.set_point_temperature = -40
271        bms_hardware.max_time = 3600
272        bms_hardware.run_resting_cycle()
273        bms_hardware.thermal_chamber.set_point_temperature = 25
274        bms_hardware.max_time = 5 * 60
275        bms_hardware.run_resting_cycle()
276        bms_hardware.thermal_chamber.set_point_temperature = 60
277        bms_hardware.max_time = 3600
278        bms_hardware.run_resting_cycle()
279        bms_hardware.thermal_chamber.set_point_temperature = 25
280        bms_hardware.max_time = 5 * 60
281        bms_hardware.run_resting_cycle()

Measure open circuit voltage
Temp Cycle in thermal chamber per MIL-STD-202, method 102 (now 107), letter D:

Bring pack to -40C (+0, -5) for 1 hour
Bring pack to 25C (+10, -5) for no more than 5 minutes
Bring pack to 60C (+5, -0) for 1 hour
Bring pack to 25C (+10, -5) for no more than 5 minutes
Repeat preceding 4 steps 5 times

Inspect for any physical/mechanical defects
Measure open circuit voltage

@pytest.mark.skipif(REST_TIME == 0, reason='Resting not requested')

def test_resting(): View Source

284@pytest.mark.skipif(REST_TIME == 0, reason="Resting not requested")
285def test_resting():
286    """Record resting data."""
287    bms_hardware.max_time = REST_TIME
288    bms_hardware.sample_interval = SAMPLE_INTERVAL
289    bms_hardware.run_resting_cycle()

Record resting data.