DA14680 - charging lithium button cell battery

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JohannesG
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Last seen:3 years 4 months ago
加入:2017-09-08 08:28
DA14680 - charging lithium button cell battery

Hello there,

I want to charge a rechargeable lithium button cell battery (LIR 2450) with the DA14680 Development Board.
I tried the example of the Software Platform Reference, but it doesn't work! The battery stops to discharge when I connect a Voltage to VBUS (5V) but the charging doesn't starts.

When I tried it with two Ni-MH batteries, it charged.
Does anybody now a solution?

----------------------------------------------------------------------------------------------------------------
Connection: the poitive terminal to VBAT from the Controller and the negative terminal to GND
Software: SDK_BTLE_v_1.0.8.1050. The code which I changed in the "custom_config_qspi.h" is attached below.

LIR 2450 Infos:
- Nominal Capacity: 120 mAh
- Charging Voltage: 4.2 V
- Nominal Voltage: 3.6 V
- Standard Charge Current: 60mA // max. 120mA
- End of Discharge Voltage: 2.75 V

----custom_config_qspi.h--------------------------------------------------------------------------

#define dg_configBATTERY_TYPE (BATTERY_TYPE_CUSTOM )
#定义dg_configBATTERY_CHARGE_VOLTAGE 0xA // 4.2V
#define dg_configBATTERY_TYPE_CUSTOM_ADC_VOLTAGE (3440) //(4095 * 4.2 V) / 5

#define dg_configPRECHARGING_THRESHOLD (2462) // 3.006V

#define dg_configCHARGING_THRESHOLD (2498) // 3.05V

#定义dg_configBATTERY_CHARGE_CURRENT 4 // 60mA

#define dg_configBATTERY_PRECHARGE_CURRENT 20 // 2.1mA

#定义dg_configBATTERY_CHARGE_NTC 1 // disabled
#define dg_configPRECHARGING_TIMEOUT (30 * 60 * 100) // N x 10msec

Device:
MT_dialog
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Last seen:2 months 2 weeks ago
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加入:2015-06-08 11:34
Hi JohannesG,

Hi JohannesG,

Even if the settings that you have aren't proper the worst case is that the battery will be damaged but this will occur most probably at the end of the charging period, there is no actual reason for the battery that you have mentioned not to be charging at all and with a different battery to be able to charge, so what i can only imagine is either a faulty connection or a damaged battery. Whatever your settings are in the battery configuration definitions it will prevent it from an optimal charging but it wont prevent the battery from charging at all. Also since you mention that the lithium is a coin cell battery, i suppose that you are placing the battery in the holder below the daughter board, that means that you will have to switch the daughter board switch from VBAT to COIN.

Thanks MT_dialog