EEVblog Electronics Community Forum
Electronics => Beginners => Topic started by: Adhith on July 20, 2018, 07:09:46 pm
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hello everyone...
I have been so far familiar with connecting 18650 Li ion cells in series its charging and attaching BMS and all. For more power hungry projects connecting these cells in parallel is demanding but I have no idea about what all things is to be considered while doing so.
I know one of the important things to consider is that the cells suppose be connected in parallel should be of the same charge to prevent the uncontrolled charging of the weaker cell. So is there any other things to consider while doing this??
Also the cells in series could be easily monitered by connecting a BMS but what about the cells in parallel?? is there any circuitry to monitor that both the cells are charging the cells at the same rate so that one cell wont charge the other
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The level of charge would need to be equalized, ie the cells would need to be at the same voltage.
Otherwise a large current may flow upon contact.
You can do this with a 10 ohm resistor.
Once connected in parallel they will effectively be one large cell.
For regular charging and discharging you would not need to monitor each cell.
If you want to know the health of individual cells you must add a way to disconnect them for testing.
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The level of charge would need to be equalized, ie the cells would need to be at the same voltage.
Otherwise a large current may flow upon contact.
You can do this with a 10 ohm resistor.
Once connected in parallel they will effectively be one large cell.
For regular charging and discharging you would not need to monitor each cell.
If you want to know the health of individual cells you must add a way to disconnect them for testing.
Thank you very much for the reply.