XIAO ESP32-S3 & Wio-SX1262 : using a NCM 18650 as a battery

Products & Technology XIAO
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I have two questions about battery use with the XIAO ESP32S3 & Wio-SX1262 Kit Introduction | Seeed Studio Wiki :

  1. the wiki/documentation states that a LiPO battery should be used, can I use a NCM18650 battery ? (Lithium nickel manganese cobalt oxides)
  2. I have batteries with no circuit protection, is that OK and if not what are the risks for the boards ?

Thanks in advance !

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It shouldn’t be an issue because the SGM40567-4.2XG on the XIAO ESP32-S3 supports NCM.

But, it charges at 110mA (XIAO 'S3 default) so charging could take a “while” - depending on your battery rating.
Another issue is that it won’t protect your battery from “over-discharge”.

In a “pinch” the XIAO’s battery support can be used for quite a few battery powered devices, but for more “demanding” requirements (and “unprotected” batteries), I tend to prefer an “off-board” power management system.

When the battery gets low I ensure it is disconnected but not before sending the XIAO a “warning”.

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I’ve added a battery voltage measurement with a voltage divider, so could the “over-discharge” risk be mitigated by shutting down the xiao when low voltage is detected ?

Interesting the 110mA current limitation… So if the device is powered by a solar panel with usb output, if that solar panel provides more than 110mA it won’t charge faster… That could be a good argument to add a “off-board” power management system…

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Correct.

ESP32-S3 is quite “power hungry” so if you don’t need the BLE/WiFi, dual core etc, then I’d go for a “smaller” CPU.

For a “non-onboard-battery-charger” solution, I’d go with the XIAO SAMD21. I use a solar panel with on-board battery (+BMS) and USB C power cable.

I also use the XIAO MG24 due to very low power consumption (it charges at 200mA but draws almost no power).

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