Which battery chemistries can I use for an Adafruit bq24074 solar BMS?

The Adafruit production description for their bq24074 solar charger says to only use Adafruit branded batteries. They recommend buying only Adafruit (max 4.2V, nominal 3.7V) batteries for this solar charge controller.

How strictly should we tolerate those stated constraints on the board? For example, safe to use max 4.2V, nominal 3.6V batteries here?

What exactly is LiPoly, compared to "Li-Ion", "LiFePO", and similar Lithium-based battery chemistries? Generally speaking, is it okay to mix and match different Lithium batteries and Lithium chargers?

What about these other batteries:

  • Samsung 25R Li-Ion 18650 max 4.2V, nominal 3.6V
  • Samsung 30T 21700 max 4.2V, nominal 3.6V
  • generic Li-Ion CR2032 3.3V
  • generic Li-Ion 9v
  • generic Li-Ion AA, AAA 1.7V - 5V
  • generic NiMH AA, AAA 1.7V - 5V
  • generic LiFePO


Thanks for the question!
Being an old fox used to lead batteries, and some NiMH lately I'll follow the replies to Your question.

Any brand of battery using the same technology as the Adafruit cells ought to be safe. Let's se what the experts say.

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The device is a charger. A Charger is not a Solar Controller. I am sure the batteries they want you to buy have a BMS built in that is matched to the solar charger.

That solar charger cannot charge 12V LiFePo4 batteries.

If you are going to run a project off a battery charged by solar then you want a charge controller. Their are either PWM or MPTT.

LiPo batteries can be used in a solar project whiles the batteries are being "charged". The batteries will last about 4 months, my experience, and the batteries will not charge if they get to hot and if they freeze throw them away.

That solar charger cannot do the LiFePo4 thing.

I gather the DD08CRMA charger would be even worse for this project, since it has no way to send battery power to other devices. Right?

Same for SD05CRMA as well. These appear to be able to charge batteries, but I have no idea how one would safely draw power from the batteries without physically pulling out the batteries from the charger and manually reinserting them into another part of the system.

Hmm, I am having trouble with all this terminology. I tried Googling variations of "arduino solar bms controller" and this is what I got.

What about the DFR0559? Is that a "solar controller"? And the DFR0264?

Do I need anything beyond a simple battery holder to safely use the DFR0559 / DFR0264 to solar power my microcontroller?

I solved the issue of Li batteries and solar by switching over to LiFePo4 batteries and PWM charge controllers.

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