LiPo connection on CubeCell PCB

I can see where to connect a solar panel to the CubeCell PCB, but where do I connect the LiPo, and are there any details as to suitable battery capacity? Is the charging circuitry really on-board? It’s shown as a block diagram, but no details.


the lipo connector is on the lower side (xh 1.25mm) of the PCB.
I am using lipos with 100mAh to 4000mAh without problems.

For some reason I was expecting a couple of solder pads…

I just received my order for the LiPo batteries from my supplier. Wow these batteries are tiny! This is a question for anybody with experience using a LipO on either the capsule or dev board or USB board.
Does the battery get charged when you connect the battery at the same time as connecting the USB to a PC?
@rsmedia, are the current polarities on the dev board and USB board a direct match to the JST GH connectors - from the battery to the connectors on the PCBs? ( ie one does not need to rewire anything?)
Also can anyone share what solar panels they have tested for the CubeCell series? Links (URL) to suppliers would be appreciated. @Sivaelid what has worked for you?

@Supporter, what is the status of the power cable modification to the capsule. To prevent any accidents and maintain the quality post manufacturing, it would help if a power lead is pre installed so that one could just plug the battery in. How long does a fully charged battery last if not being charged by a solar panel. What example (brand) of solar panel has Heltech used for tests? A link (URL) to such suppliers would be appreciated

The lipo is charged when connecting the device to usb. How long the lipo can power the device depends on the dutycyle and the sensors used.
I have a capsule with a bme280 sensor and a 100mah lipo and a dutycycle of 15min running for 2 weeks now and the rememaining charge is ok. It should run approx 1-3 month.

You have to look at the polarity of the lipo before connecting it to the dev or usb board.
Most china lipos have the right polarity but some ate reversed.

Thanks @rsmedia. I installed one of the LiPos on a dev board and it appears all the batteries that came are wired correctly.

Something that I forgot to ask you, how did your tests on the board you gave me the gerber files do in your tests. I haven’t had time to test the copy pcbway built yet. I mean this one

Now that I have 20 batteries I need to get the female JST GH connectors and solder them to the capsule. Which solar panels have you had success with so far?

the board is running fine but i am not using it anymore.
i am using now 2 new boards:

1 for a nice little indoor node with an BME680 or BME280 sensor (the battery is not final, there will be an 18650 Lipo in the future:

and 1 for the outdoor modular node. this is using a TCA9548A I2C 8 port switch: ( you can now use up to 8 sensors of the same type, 8 BME680 for example each on 1 port.):

This outdoor node is packaged in an IP65 rated housing:

on top of the housing will be a Solar panel with 5.5V 160mAh:

all 8 I2C Sensor Ports (4pol), the OneWire Port(3pol) and a port for an external solar panel (2pol) will be accessible with ip65 rated connectors to the outside.

Hi Gipsyblues I am only going to use the CubeCell capsule for package shock detection in transit.

My experience is the capsule and Board are the same electronics, I have focused on the Board Version as far more useful for me and will be basing some nodes on it, now I am happy with the software and hardware.

On the use of LiPo I have both 80mAh and 100mAh LiPo for the CubeCell and if you think the 100mAh is small you need to see the 80mAh, it seems so much smaller.

On solar cell charging I have used both Mono-Crystalline and Poly-Crystalline versions and in the range from 5- 7.5 volts (this is 10 to 14 cells), I based mine on 6 volts but 5.5volys is as good.

You ask about battery life , I put up a few months ago a battery life calculator on one of my sites that will help you with the SF/duty cycle etc.

On the solar cell size, then just base it on say a factor of two on the average daily use of the node. Typically in the UK for example 4-5 hours of poor sun light and with a 60 ma Solar cell this is keeping my nodes fully charged when set at sf 7-12 and duty cycle of 20 minutes TX 14dbm.

Happy Festive period Simon

I ordered these, believing that the connector would fit(it is shown as compatible with the Heltec ESP32/LoRa module, after all). It does sort of fit, but only with the application of brute force. Doesn’t feel right…

the micro jst is a little to wide but will fit with a good amount of force.
the right connector is the XH1.25.
the connector has a tight fit

@rsmedia Thanks for sharing. Could you kindly share links of i2c expansion board and ip65 rated connectors. Also can we connect different type of sensors to these expansion board.


There is a lot of misinformation out there when it comes to describing JST connectors. I have been in the industry that uses these type of connectors for a pretty long time and I hope I can shed some light on this confusion.

Please note there is nothing like XH1.25 - a creation by suppliers who have no clue as to what they are saying. a JST connector which has 1.25mm spacing is officially called a JST GH , there really is nothing like JST XH 1.25. The pitch of XH is 2.5mm not 1.25mm

Data about JST XH connectors from the horses own mouth

For a JST-GH, please see
Official specs of a JST GH connector

The connector on the Heltec CubeCell boards - at least the USB adapter and the dev board are all true JST GH connectors - 1.25mm pitch

If a supplier insists that the pitch of a JST connector product he/she is selling is 1.25mm then ignore the XH designation he/she is touting. An XH connector is 2.5mm and would definitely not fit a 1.25mm connector (male/female)

I hope this helps in wading through all the confusion being generated by the sellers out there

good to know thank you @Gipsyblues

but the gh connectors look different they are lockable.
the used connectors looks like the xh series but with a 1.25mm pitch
so it could be a hirose df-13 or a molex picoblade

i think they are molex picoblade

I have attached a copy of a sales ad to this message. These are JST-GH 2 pin cables.
Just to clear any potential confusion

The cable to the right (the male) is what Heltec has been including with the dev board. Also that is the same cable the 3.7v 100mAH LiPo battery comes with. The cable to the left is the female and that is what they should have installed on the capsule PCBs

You are more savvy than most of the guys on the forum, however I would suggest that you pay attention to the vocabulary, to what most of the sellers use. I hope your business grows so large that if you have to place a large order, you don’t allow the supplier to waste your time by shipping you the wrong product - especially if you are buying from non Aliexpress or Alibaba suppliers

You have no idea what I have learnt from you in this short period I have had the good luck to interact with you! Keep up your great work

This I2C expansion board is part of our MoularNode:

right now we are not selling the board alone, but we are planing to sell the boards.

if you use our firmwares and the CubeCell Configurator found here:

you can use this I2C sensors:

  • ADS1015/ADS1115
  • BH1750
  • BME680
  • BME280
  • BMP180
  • BMP280
  • CCS811
  • HDC1080
  • MPU9250
  • SHT2x

The IP65 rated connectors are GX16 and are found on aliexpress:

or if you like metal plugs GX12:

Thanks @rsmedia . Really appreciated. Looked at the modular outdoor node which is listed in the website. Will be nice if it can have or have an option to have an external antenna. Please let me know once you start selling the board. Mean time i found this one in the ali express. Is below board okay ?


My current project involve creating a node which has environmental sensors and a water leak sensor. For the environmental sensor my plan was to go with BME680 as it has temp/pressure/humidity and voc. But after seeing this comparison post! i am thinking to use BME680 or not… Do you have any suggestion ?

I will definitely try your Configurator once i get my development boards.

Thank you

Yes that i2c switch will work it is the same ic that i use.

The modular node has the possibility to attach an external antenna.

I use the BME680 in most cases.
The mjmcu-8128 board (hdc1080, ccs811, bmp280) is good too but more power hungry.