Hello,
does anyone know if the nano 33 ble sense can be powered by a battery pack and how?
I've searched the forum and the product documentation but I couldn't find any reference / project that explain if that's possible (I suppose it is) and how to do it.
thanks.
The easiest way to power these boards with a battery is to use a USB battery pack connected to the USB socket on the board. Note that some of the more fancy battery packs require a fair amount of current draw to turn on, so they are not well suited to powering the Nano 33 BLE Sense.
Thanks Pert for your quick reply.
if the fancy ones are not suitable, is there any that you would recommend (perhaps one that you've already used personally and know that works)?
thanks a mill,
Stefano.
I just have the no-name super cheap one from a Chinese seller on eBay. I would hesitate to recommend those since LiPo batteries are always a bit sketchy, and even more so when you buy one for $1.50 with free shipping from the other side of the planet.
ha ha, that's fine. if a non branded pack work, I should be safe with a mid-range one from any of the local shops. I just wanted to make sure that there were no voltage/amp restrictions that I have to make sure to meet. don't want to burn the little guy the very first day.
thanks for your assistance.
The USB battery packs are always 5 V. As long as you are applying 5 V to the USB socket on the board, that is perfectly fine.
As for amp rating of a battery pack, this would refer to the maximum current the pack can supply. The board will only draw as much as it needs. So even if the board only needs 0.1 A, you could connect a 10 A battery pack to it and it would not cause any problems. The 10 A doesn't mean the battery pack is going to somehow pump 10 A into your Arduino board.
Most often you will see a mAh rating on the battery packs. That tells you the battery capacity. a higher number means the board will be able to run longer on the battery before it needs to be recharged.
Awesome,
Thanks for your help pert
That was extrmely useful.
You answered all my questions.
You're welcome. I'm glad if I was able to be of assistance. Enjoy!
Per
Use this one:
Martin
Hi everyone,
Wanted to hijack this forum thread and go a little deeper into if I do not want to/can use an external power bank and would like to use the USB port as the charger port for a couple 18650 batteries.
The nano 33 ble has the 5V pin of the micro usb port attached to one of the Arduino output pins given that you make the solder joint connection on the back of the Arduino. I am thinking to use this pin and one of the ground pins to connect the batteries to.
Looking at the box of the nano 33 ble the Vin pin can handle 4.5 - 21V. This is where I want to connect the power output to.
I am guessing the the voltage of 4.2V - 3V of a single 18650 or parallel connected 18650 is too big of a voltage range to connect to the 3.3V pin directly (I do not like toasted arduinos 
)
So what I am thinking is to use a 2S (2 cells in series) configuration. Let's start with 2S1P and see how much on time it will give me. This will give me a voltage of 8,2V - 6V. I am guessing that going 3S or 4S will make the whole setup less efficient. I am guessing this because it's probably converted to heat by some regulator chip on the Nano. I am not sure about this. Please share your knowledge if you know.
As for the BMS I see that the more expensive ones offer 4 main features:
Is there some feature more that I should look out for when choosing a BMS?
I have 3 18650 batteries laying around atm of which I am planning to use just 2 in the 2S1P configuration mentioned above.
So for the 2S1P configuration I would probably not need the balance charge feature as this is only used if I use multiple cells in parallel but because my configuration right now is 1P I do not theoretically need this?
Knowing all this I stumbled upon this 2S BMS system:
These are its specifications: (in case this listing goes down in the future)
Model: HX-2S-JH20 over voltage range: 4.25~4.35v±0.05v
Size: 46.7233.15mm over discharge voltage range: 2.5-3.0v ±0.05v
Upper working current: 10A operating temperature: -40---+50
Limited current: 20A storage conditions: -40-- +80 C
Balanced detected voltage: 4.20V±0.05V
Balanced release voltage: 4.20V±0.05V
Balanced current: 0.45mA
Quiescent current: less than 10uA useful life: more than 50000 hours
Resistance: less than 300m ohm short circuit protection: protection, charge recovery
Charging Voltage Range: 8.4V~9.0V
Size: 46.7233.15mm
The only thing making me scratch my head is the charging voltage range 8.4 - 9V.
Can I use the micro USB 5V and boost it up with some boost converter to meet this requirement to boost the batteries?
Marked all my questions in bold text so you can find them more easily 
Thanks in advance for your feedback!
I am still quite confused by the BMS boards one of which I mentioned above. Another way would be to just use one 18650 cell with one of these boards:
featuring a TP4056 IC
and a DW01 IC
Connect the plus charger pad of this board to the VBUS 5V pin of the Nano. One 18650 to B+ and B- and the output pads directly to the Nano’s 3v3 pin through a BUCK-BOOST DC/DC converter. See this topic of the electronics.stackexchange forum
For me this approach is way less confusing. However I think this way I am missing a lot of safety features i’d have with the more robust BMS from the last post.
