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I'm planning on designing a system to charge multiple 3.7V 500mAh lithium-ion batteries simultaneously. The batteries are each going to be charged through a battery charger IC, here is the link to the datasheet.

I'm planning to employ the fast charge constant-current mode with a charge current of 500mA. I've tested it for a single battery and it works perfectly.

Now I want to scale it up to charge 10 or more batteries at once, so the system consists of a 5V 60A DC switching power supply and the batteries and its ICs connected in parallel between the outputs of the power supply.

Since I'm charging many batteries at once with each pulling 500mA, the main supply line coming from the power supply will carry a high current. I'm not sure if this will damage the ICs, or if this design is feasible. For example, if I intend to charge 10 batteries simultaneously with each at 500mA, the main supply line would carry 5A. Will this current be too high for the battery charger ICs and will each battery charger IC only pull the required 500mA of current from the main supply line? Will this design work, and can it scale to even larger numbers?

Thanks.

Edit: Many of the previous posts I have seen mention soldering the leads of batteries together and charging them in aprallel using a single battery charger IC. Mine is slightly different. It uses a separate battery charger IC for each cell but those ICs are arranged in parallel like the picture shown below. The IC is capable of monitoring the voltage of the battery, so I guess this design would not have issues of some batteries discharging to charge other batteries. I'm still not sure if this design will work, and if the main branch carrying the high current is a cause of concern, if each battery charging IC is pulling 500mA, 10 of them in parallel would result in 5A in the main line. Would a person touching the main line risk getting electrical shock?

enter image description here

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will each battery charger IC only pull the required 500mA of current from the main supply line?

Yes.

Will this design work, and can it scale to even larger numbers?

Yes, so long as the power supply wires are thick enough to handle the current without excessive voltage drop.

Would a person touching the main line risk getting electrical shock?

No. 5V is not a high enough voltage to cause an electric shock. However if the supply rails are exposed then they could be shorted out by a metal object (eg. a ring or bracelet) which could heat up or even vaporize if the available current is high enough.

For safety and to reduce wire size you might consider splitting the supply line into several sections, each with its own feed wires from the power supply. Each section could also be separately fused at a current not much higher than the maximum number of chargers in it. For even better protection you could put a fuse in line with every charger, then if any one shorts out it won't affect the other chargers.

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