Lii500 - Revision history

WikiSysop: /* Buck Converter (Charger) */

2021-04-08T05:21:52Z

Buck Converter (Charger)

← Older revision		Revision as of 05:21, 8 April 2021
Line 20:		Line 20:
	[[File:Ccr_v20_buck_simple.png\|thumb\|center\|400px\|Simplified buck circuit schematic for the CCR v2.0.]]		[[File:Ccr_v20_buck_simple.png\|thumb\|center\|400px\|Simplified buck circuit schematic for the CCR v2.0.]]

	The input is decoupled with a single 220uF/25V electrolytic capacitor. The charger consists of a APM9435 P-channel MOSFET, rated for up to 30V, 5.3A, 90mOhm at Vgs = 4.5V, up to 2.5W power dissipation, switched at 62.5kHz with a 47uH(?) through-hole inductor, through an SS34 ~~didoe~~, to a 22uF (?) MLCC output capacitor. Current is measured through a 0.3 ohm sense resistor.		The input is decoupled with a single 220uF/25V electrolytic capacitor. The charger consists of a APM9435 P-channel MOSFET, rated for up to 30V, 5.3A, 90mOhm at Vgs = 4.5V, up to 2.5W power dissipation, switched at 62.5kHz with a 47uH(?) through-hole inductor, through an SS34 diode, to a 22uF (?) MLCC output capacitor. Current is measured through a 0.3 ohm sense resistor.

	Charge is terminated when the current drops below 60mA in CV mode. There is no rest period before discharge begins.		Charge is terminated when the current drops below 60mA in CV mode. There is no rest period before discharge begins.

WikiSysop: /* Opus Performance Evaluation */

2020-02-06T06:59:14Z

Opus Performance Evaluation

← Older revision		Revision as of 06:59, 6 February 2020
Line 43:		Line 43:
	The Lii-500 uses an unknown microcontroller in 20-SOP packages.		The Lii-500 uses an unknown microcontroller in 20-SOP packages.

	===~~Opus~~ Performance Evaluation===		===Lii-500 Performance Evaluation===
	[[File:~~Current_ramp_0-1A~~.png\|thumb\|center\|400px\|Charging mode ramp from 0 to 1A (CC)~~.]]~~		[[File:x.png\|thumb\|center\|400px\|Charging mode ramp from 0 to 1A (CC).]]
	~~[[File:IR_current_pulse.png\|thumb\|center\|400px\|Discharge current pulse of 1A for measuring cell IR~~.]]

	~~The CCR v2 was assembled 2/15/19 and checked for basic operation cycle testing a Samsung 25R~~. ~~Charging current is limited to approximately 2A due to power dissipation of the SOIC-8 P-channel MOSFETs~~. This may improve slightly with proper airflow routing using a 3D printed enclosure. Transient performance and current regulation were measured with a Rigol DS1052E. Discharge shows an overshoot of approximately 18% for 580us, and regulation of +/-3.8% at 1A. Charge shows no overshoot, and regulation of +/-3.9% at 1.5A.		...

	~~[[File:CCR_v2_Thermal_Charging3p5A180k.JPG\|thumb\|center\|400px\|Thermal image of the P-channel MOSFET at 180kHz switching frequency, 3.5A charging. Peak was 103 C from 12V supply.]]~~

	Further investigation showed the MOSFET driver was not able to produce sharp edges, causing higher switching losses at 360 kHz. Changing the code to operate the MOSFETs at 180 kHz allows charging at up to 3.5A.

	==BOM Cost Estimate==		==BOM Cost Estimate==

WikiSysop: /* List of Features */

2019-05-01T23:36:31Z

List of Features

← Older revision		Revision as of 23:36, 1 May 2019
Line 10:		Line 10:
	* Efficiency: xx% (charging, single slot at 1A, 3.8V)		* Efficiency: xx% (charging, single slot at 1A, 3.8V)
	* Modes: Charge, Nor Test (C/D/C), Fast Test (D/C)		* Modes: Charge, Nor Test (C/D/C), Fast Test (D/C)
	* 10mV voltage resolution (3 digits), ~~xHz~~ update rate		* 10mV voltage resolution (3 digits), >6Hz update rate

	==Electronics==		==Electronics==

WikiSysop: /* Buck Converter (Charger) */

2019-04-10T01:09:20Z

Buck Converter (Charger)

← Older revision		Revision as of 01:09, 10 April 2019
Line 20:		Line 20:
	[[File:Ccr_v20_buck_simple.png\|thumb\|center\|400px\|Simplified buck circuit schematic for the CCR v2.0.]]		[[File:Ccr_v20_buck_simple.png\|thumb\|center\|400px\|Simplified buck circuit schematic for the CCR v2.0.]]

	The input is decoupled with a single 220uF/25V electrolytic capacitor. The charger consists of a APM9435 P-channel MOSFET, rated for up to 30V, 5.3A, 90mOhm at Vgs = 4.5V, up to 2.5W power dissipation, switched at ~~xxkHz~~ with a 47uH(?) through-hole inductor, through an SS34 didoe, to a 22uF (?) MLCC output capacitor. Current is measured through a 0.3 ohm sense resistor.		The input is decoupled with a single 220uF/25V electrolytic capacitor. The charger consists of a APM9435 P-channel MOSFET, rated for up to 30V, 5.3A, 90mOhm at Vgs = 4.5V, up to 2.5W power dissipation, switched at 62.5kHz with a 47uH(?) through-hole inductor, through an SS34 didoe, to a 22uF (?) MLCC output capacitor. Current is measured through a 0.3 ohm sense resistor.

	Charge is terminated when the current drops below 60mA in CV mode. There is no rest period before discharge begins.		Charge is terminated when the current drops below 60mA in CV mode. There is no rest period before discharge begins.

WikiSysop: /* FET Discharger */

2019-04-10T00:56:16Z

FET Discharger

← Older revision		Revision as of 00:56, 10 April 2019
Line 29:		Line 29:
	[[File:Ccr_v20_boost_simple.png\|thumb\|center\|400px\|Simplified boost circuit schematic for the CCR v2.0.]]		[[File:Ccr_v20_boost_simple.png\|thumb\|center\|400px\|Simplified boost circuit schematic for the CCR v2.0.]]

	The battery positive goes through a 0.3 ohm current sense resistor to the drain of an FQP30N06 N-channel MOSFET (30A, 60V, 40mOhm at Vgs = 10V, 79W power capability, ~2.16W max dissipation with 40C ambient, equivalent to 0.51A at 4.2V). The PWM rate for the MOSFET is xx kHz. The peak battery current for a 4.2V Li-Ion battery is approximately ~~xxA~~ pulsed~~, accounting for voltage drops in the FET and current sense resistor~~.		The battery positive goes through a 0.3 ohm current sense resistor to the drain of an FQP30N06 N-channel MOSFET (30A, 60V, 40mOhm at Vgs = 10V, 79W power capability, ~2.16W max dissipation with 40C ambient, equivalent to 0.51A at 4.2V). The PWM rate for the MOSFET is 62.5 kHz, with 62ns PWM resolution (1/(16 MHz)). The peak battery current for a 4.2V Li-Ion battery is approximately 0.8A pulsed.

	Discharge termination is when the Li-Ion battery reaches 2.85V at constant current.		Discharge termination is when the Li-Ion battery reaches 2.85V at constant current.

WikiSysop: /* FET Discharger */

2019-04-10T00:40:39Z

FET Discharger

← Older revision		Revision as of 00:40, 10 April 2019
Line 31:		Line 31:
	The battery positive goes through a 0.3 ohm current sense resistor to the drain of an FQP30N06 N-channel MOSFET (30A, 60V, 40mOhm at Vgs = 10V, 79W power capability, ~2.16W max dissipation with 40C ambient, equivalent to 0.51A at 4.2V). The PWM rate for the MOSFET is xx kHz. The peak battery current for a 4.2V Li-Ion battery is approximately xxA pulsed, accounting for voltage drops in the FET and current sense resistor.		The battery positive goes through a 0.3 ohm current sense resistor to the drain of an FQP30N06 N-channel MOSFET (30A, 60V, 40mOhm at Vgs = 10V, 79W power capability, ~2.16W max dissipation with 40C ambient, equivalent to 0.51A at 4.2V). The PWM rate for the MOSFET is xx kHz. The peak battery current for a 4.2V Li-Ion battery is approximately xxA pulsed, accounting for voltage drops in the FET and current sense resistor.

	Discharge termination is when the Li-Ion battery reaches 2.~~75V~~ at constant current.		Discharge termination is when the Li-Ion battery reaches 2.85V at constant current.

	===LCD===		===LCD===

WikiSysop: /* Buck Converter (Charger) */

2019-04-10T00:20:05Z

Buck Converter (Charger)

← Older revision		Revision as of 00:20, 10 April 2019
Line 22:		Line 22:
	The input is decoupled with a single 220uF/25V electrolytic capacitor. The charger consists of a APM9435 P-channel MOSFET, rated for up to 30V, 5.3A, 90mOhm at Vgs = 4.5V, up to 2.5W power dissipation, switched at xxkHz with a 47uH(?) through-hole inductor, through an SS34 didoe, to a 22uF (?) MLCC output capacitor. Current is measured through a 0.3 ohm sense resistor.		The input is decoupled with a single 220uF/25V electrolytic capacitor. The charger consists of a APM9435 P-channel MOSFET, rated for up to 30V, 5.3A, 90mOhm at Vgs = 4.5V, up to 2.5W power dissipation, switched at xxkHz with a 47uH(?) through-hole inductor, through an SS34 didoe, to a 22uF (?) MLCC output capacitor. Current is measured through a 0.3 ohm sense resistor.

	Charge is terminated when the current drops below ~~xmA~~ in CV mode. There is no rest period before discharge begins.		Charge is terminated when the current drops below 60mA in CV mode. There is no rest period before discharge begins.

	===FET Discharger===		===FET Discharger===

WikiSysop: Created page with "This is an analysis/reverse engineering review of the Liitokala Lii-500 Engineer 4-slot Li/Ni battery charger/tester. File:CCR_v1_Regen.jpg|thumb|right|Fully functional v1..."

2019-04-09T23:16:28Z

Created page with "This is an analysis/reverse engineering review of the Liitokala Lii-500 Engineer 4-slot Li/Ni battery charger/tester. File:CCR_v1_Regen.jpg|thumb|right|Fully functional v1..."

New page

This is an analysis/reverse engineering review of the Liitokala Lii-500 Engineer 4-slot Li/Ni battery charger/tester.

[[File:CCR_v1_Regen.jpg|thumb|right|Fully functional v1 CCR prototype in regenerative configuration, testing Re-volt and Samsung 2600mAH cells.]]

==List of Features==

* Voltage Range (Charge): 0-4.2V
* Max Current (Charge): 1A
* Max Current (Discharge): 0.5A
* Efficiency: xx% (charging, single slot at 1A, 3.8V)
* Modes: Charge, Nor Test (C/D/C), Fast Test (D/C)
* 10mV voltage resolution (3 digits), xHz update rate

==Electronics==
===Buck Converter (Charger)===
Reverse polarity protection is achieved by use of a low-side N-channel MOSFET (LTC8205A) rated for 6A, 20V, 38mOhm at Vgs = 2.5V, up to 0.83W power dissipation.

A simplified schematic of the buck converter that charges the battery from a 12V supply is shown in the thumbnail below:

[[File:Ccr_v20_buck_simple.png|thumb|center|400px|Simplified buck circuit schematic for the CCR v2.0.]]

The input is decoupled with a single 220uF/25V electrolytic capacitor. The charger consists of a APM9435 P-channel MOSFET, rated for up to 30V, 5.3A, 90mOhm at Vgs = 4.5V, up to 2.5W power dissipation, switched at xxkHz with a 47uH(?) through-hole inductor, through an SS34 didoe, to a 22uF (?) MLCC output capacitor. Current is measured through a 0.3 ohm sense resistor.

Charge is terminated when the current drops below xmA in CV mode. There is no rest period before discharge begins.

===FET Discharger===
A simplified schematic of the circuit that discharges the battery is shown in the thumbnail below:

[[File:Ccr_v20_boost_simple.png|thumb|center|400px|Simplified boost circuit schematic for the CCR v2.0.]]

The battery positive goes through a 0.3 ohm current sense resistor to the drain of an FQP30N06 N-channel MOSFET (30A, 60V, 40mOhm at Vgs = 10V, 79W power capability, ~2.16W max dissipation with 40C ambient, equivalent to 0.51A at 4.2V). The PWM rate for the MOSFET is xx kHz. The peak battery current for a 4.2V Li-Ion battery is approximately xxA pulsed, accounting for voltage drops in the FET and current sense resistor.

Discharge termination is when the Li-Ion battery reaches 2.75V at constant current.

===LCD===
The display uses an unmarked LCD Driver Controller/microcontroller.

===CCR v1 Performance Evaluation===
[[File:CCR_v1_Efficiency.png|thumb|center|400px|Buck (charging)/Boost (discharging) converter efficiency for the CCR v1.0.]]
[[File:Thermal_4V-1p5A.JPG|thumb|right|Boost (discharging) mode operation at 1.5A, showing peak external transistor temperature of 57.8 C.]]

===Microcontroller===
The Lii-500 uses an unknown microcontroller in 20-SOP packages.

===Opus Performance Evaluation===
[[File:Current_ramp_0-1A.png|thumb|center|400px|Charging mode ramp from 0 to 1A (CC).]]
[[File:IR_current_pulse.png|thumb|center|400px|Discharge current pulse of 1A for measuring cell IR.]]

The CCR v2 was assembled 2/15/19 and checked for basic operation cycle testing a Samsung 25R. Charging current is limited to approximately 2A due to power dissipation of the SOIC-8 P-channel MOSFETs. This may improve slightly with proper airflow routing using a 3D printed enclosure. Transient performance and current regulation were measured with a Rigol DS1052E. Discharge shows an overshoot of approximately 18% for 580us, and regulation of +/-3.8% at 1A. Charge shows no overshoot, and regulation of +/-3.9% at 1.5A.

[[File:CCR_v2_Thermal_Charging3p5A180k.JPG|thumb|center|400px|Thermal image of the P-channel MOSFET at 180kHz switching frequency, 3.5A charging. Peak was 103 C from 12V supply.]]

Further investigation showed the MOSFET driver was not able to produce sharp edges, causing higher switching losses at 360 kHz. Changing the code to operate the MOSFETs at 180 kHz allows charging at up to 3.5A.

==BOM Cost Estimate==

{| border="1" style="text-align:center;"
|'''EE Component'''
|'''Cost'''
|'''Source'''
|- style="color:gray;text-align:left;"

|OPA335 Zero-Drift Amplifier (qty 2)
|$2.42
|[https://lcsc.com/product-detail/Others_Texas-Instruments-TI-OPA335AIDBVR_C364887.html LCSC]
|- style="color:gray;text-align:left;"

|MCP1402 MOSFET Driver (qty 4)
|$1.83
|[https://lcsc.com/product-detail/MOS-Drivers_MICROCHIP_MCP1402T-E-OT_MCP1402T-E-OT_C128573.html LCSC]
|- style="color:gray;text-align:left;"

|STM32F103 "Blue Pill"
|$1.82
|[https://s.click.aliexpress.com/e/cWPSibTi Aliexpress]
|- style="color:gray;text-align:left;"

|NCS199A1 Current Sense Amplifier (qty 2)
|$1.45
|[https://lcsc.com/product-detail/General-Purpose-Amplifiers_ON-Semicon_NCS199A1SQT2G_ON-Semicon-ON-NCS199A1SQT2G_C179595.html LCSC]
|- style="color:gray;text-align:left;"

|18650 SMT Holder (qty 2)
|$1.23
|[http://s.aliexpress.com/nuqmae6r Aliexpress]
|- style="color:gray;text-align:left;"

|N-channel MOSFET 13A 11.5mOhm SOIC-8 (qty 4)
|$0.52
|[https://lcsc.com/product-detail/MOSFET_Alpha-Omega-Semicon_AO4406AL_Alpha-Omega-Semicon-AOS-AO4406AL_C35349.html LCSC]
|- style="color:gray;text-align:left;"

|rBOM (under $0.41)
|$4.76
|LCSC
|- style="color:green;text-align:left;"

|PCB
|$2.00
|JLCPCB
|- style="color:purple;text-align:left;"

|Assembly
|$7.10 - $31.70
|PCBgogo
|- style="color:black;text-align:center;"

|'''HW Component'''
|'''Cost'''
|'''Source'''
|- style="color:blue;text-align:left;"

|100x40x20 Aluminum Heatsink
|$3.02
|[https://www.ebay.com/itm/5pcs-Aluminum-Heat-Sink-100X40X20MM-100-40-20MM/163423637602?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649 eBay]
|- style="color:blue;text-align:left;"

|40x40x20 5V Fan
|$1.60
|[https://www.ebay.com/itm/10-Pcs-5V-40mm-x-20mm-Cooling-Case-Fan-40x40x20mm-PC-Computer-Cooler-3D-Printer/251791125294 eBay]
|- style="color:blue;text-align:left;"

|Misc HW (Under $0.22)
|$0.42
|Aliexpress/eBay
|- style="color:red;text-align:left;"

|Total Price
|$52.41 (Assembly cost $317, batch qty 10)
|
|-

|}