Battery with bigger capacity

Hi,

I need to extend the operation of the Pi on battery for a long period of time, so I need to use another battery than the flat top unprotected 18650 battery.

What are the characteristics my battery should meet ?

  • Li-on or Li-po ?
  • 3.7V or other ?
  • a max capacity ?
  • JST-SFH connector ?

If I use an external battery, may I use the Qwiic connector with, for example, this Adafruit LC709203F LiPoly / LiIon Fuel Gauge and Battery Monitor ?

Thank you !
Regards,
Paul

Hi Paul,

Both can be used.

No maximum capacity limit. It is enough to have 1 cell 3.7V.

You can plug an external single-cell 3.7V Li-on or Li-po rechargeable batteries when bigger capacities or special dimensions needed. Use JST-SFH connector(J5) with a suitable battery cable with it or you can solder cables to battery header(J9) by paying attention to the polarity.

The HAT already has a battery gauge but if you want to use external, the J1(Qwiic connector) is directly connected to Raspberry Pi, you can use it. When using, disable the I2C pull-up resistors on your board.

Thanks.

Hello,

I understand that 1 cell 3.7V has been mentioned, but how come I can’t add 2 cells in parallel?

Especially if I try to voltage match them?
My application requires the pi to have a run time of at least 24 hours on battery.

Sincerely,
Daniel

Hi @danielrubinov97 ,

Sadly, HAT does not support this.

I have considered using a Goal Zero or Jackery power system (battery + solar) to provide autonomous power for long periods.

Depending on how much your system is doing, you might need between 5w and 20w. So for 20w a 500wh battery pack and a decent sized solar panel (probably at least 80w) should be enough to keep you going.

I’d really like to see someone partner with one of the above companies to provide a USB data interface so you could see battery and charging status on the Pi itself.

you can build a larger battery, the main thing is that you stick to a single-cell system 3.6V. I myself built a 25Ah block of 18650 cells and soldered it to the battery on the board, but then you have to tell the system the capacity. Why you do it this way is a mystery to me, it would have been better to regulate the charging via the voltage because such a battery has a range of 3 - 4.2V, especially since the voltage is measured anyway, but here the capacity + consumption + time calculated in a complicated formula. maybe you can accommodate that in the next firmware update that is calculated with the voltage…. if there is still someone working on it.