Solar charge controller for lithium batteries

Question

My project is a solar powered RC car with the ESP32. Currently, I´m looking for a solar charge controller. I have two solar panels that deliver 3,5W at 6V. I want to charge Li-Ion or LiPo batterys. I need about 3A/ 5V for my project. My idea was to use the TP4056 charge controller. I tried to get information about it, but every site I visited said something different and I´m confused right now... Here are my questions:

1. Does the TP4056 come with battery protection? (Over charge, over discharge, short-circuit-protection, ...)

2. Can I charge multiple batteries with one TP4056? If I for example would use 18650 batterys, I would need three of those in parallel to give me the ammount of current I need. Can I charge them all with one TP4056? Or would I have to charge each battery with a seperate TP4056?

3. If I would have to use three charge controllers: How would I wire them, so all batteries can be used in parallel (to give me the amount of current I need) as a power source and can all be charged at the same time?

4. Is the TP4056 even the right charge controller for my project? If no, is there another one, that you would recommend?

Thanks for your help! 🙂

Answer 1

1. No. Protection needs to be separate, unless the cells or pack already has built in protection.

2. Multiple cells in parallel is just one large cell. You can use a single TP4056 but it would just take very long to charge with 1A.

3. If the pack already has multiple cells in parallel, it is just one large cell. Not possible to charge each separately with TP4056 for each cell. You also can't use multiple TP4056s in parallel for increased current.

4. No it does not seem like suitable, but suggesting a product or what to buy is off-topic.