Charger Basen BO-1
This is a fairly simple single cell LiIon charger from Basen.
It arrived in a cardboard box with a lot of specification on it.
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The box contained the charger, a usb cable and a instruction sheet.
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The charger is usb powered with a micro usb input.
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There is only one button and a couple of leds. The button will change selected current, default is 0.5A.
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During power on all the leds will shortly turn on. During charge the blue leds are animated and only one green led is on.
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The specifications are on the bottom of the charger, but rather hard to read.
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The charger uses the classic slider construction and will handle batteries from 28mm to 70.7mm, this will give problem with the longest protected cells.
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The charger can handle up to 70mm long batteries,
Measurements
- Power consumption from usb when idle with no batteries is 18mA
- Below 0.3V the charger will not detect a battery
- Between 0.3 and 3V the charger will charge with low current
- Above 3V the charger will use full current.
- Will restart charging if voltage drops.
- Will restart charging if battery is inserted or power cycled.
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A nice CC/CV charge curve with termination current of about 35mA. The charge voltage is at the top of the allowable range.
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The two other batteries also look nice.
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There is no problem with this old cell.
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Using 0.5A also works fine.
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The low termination current is fine for smaller cells.
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And also for old worn out cells.
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The 2A current is only maintained for a short time due to voltage limitations, then it will slowly drop. The charging is faster than 1A charging.
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Adding 0.5ohm resistance in series with the power supply to simulate a long cable or weak supply shows that the charger will reduce usb and charge current, but the charging works fine.
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M1: 39.4°C, M2: 51.9°C, M3: 58.5°C, M4: 52.2°C, HS1: 60.0°C
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Being a fairly simple charger I could draw the current profile.
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The charger is very fast to start, it only needs about 1 seconds.
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It is possible to change current at any time.
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This charger handles unstable voltages nicely.
Conclusion
The high charge voltage and low termination current will mean fully charged cell, but will cost a bit lifetime for the batteries. I like the simple user interface and adjustable tray, it is easy to use and means that the charger can handle most LiIon battery sizes.
I will rate it as good.
Notes
Here is an explanation on how I did the above charge curves: How do I test a charger