Discussion Batteries

[Ben-Da-Man]

Thanks for this.

 

[Ibprofen98]

I have a couple questions about my battery setup. I have four Panasonic li-ion batteries that I will use to make 2 7.4v battery packs, and my goal is to be able to charge and play. I purchased this circuit last year, and I believe it is the right one, but I need to be sure. It's a 2s board, does that mean it will work with two 2s packs? I hope so.

My second question is, with this board, I do not need a separate protection circuit for the batteries, correct? What kind of charger do I need to use? Can it be any charger that delivers 8-9 volts at 1 Amp, or does it have to be a smart charger?

 

[Ibprofen98]

Found my answer back a little in this thread, but just to confirm, I have the batteries, the red board, will be hooking them up with 2 7.4v packs, I don't need a smart charger, I got all that down, know I don't need any other boards, just one final question, does this satisfactorily allow me to one port charge and play?

 

[medic3k]

I have an OLD wii (-01 motherboard, I still have the box as I was like 141st one sold in US) so I assume power consumption will be high, closer to 20W then 10W of a -30 or newer board. But what effect on this does the OMGWTF 6layer trim have? obviously the wifi module, power and temp safety components, and Disc Drive get axed... but I'm running a 5" LCD&Driver off 3.3v and the speakers as well, what should I expect as a total draw??

Because of the above, I'm wondering what sort of deliverable voltage should I plan for? is a 2S2P of 18650s acceptable/standard?
It would give me 7.4v and around 7Ah which seems like aprox. 2 hrs of charge (7x7.2)/(20W)*.8 with .8 being my accounting for non-perfect discharge/charge conditions and battery imperfection. Is the 7.4v required for running a Wii board? or could I get away with 1s2p?

I have batteries picked out:THESE

and a CMB, but I'm concerned on this one..., as it requires a 9-15V in for charging. I'm wanting to be able to charge off of my same power adptr as my Cellphone (USB-C 5v 2a) so I'm wondering what if any solutions the community has come up with to push a charge to a 7000mAh bank? I noted the all-in-one power management boards on the bitbuild store, but that's fairly costly given the alternatives in the wild. Not to mention I'm in no shortage of components to draft up my own PCB, just not the most skilled with power electronics

 

[jefflongo]

I have an OLD wii (-01 motherboard, I still have the box as I was like 141st one sold in US) so I assume power consumption will be high, closer to 20W then 10W of a -30 or newer board. But what effect on this does the OMGWTF 6layer trim have? obviously the wifi module, power and temp safety components, and Disc Drive get axed... but I'm running a 5" LCD&Driver off 3.3v and the speakers as well, what should I expect as a total draw??

Because of the above, I'm wondering what sort of deliverable voltage should I plan for? is a 2S2P of 18650s acceptable/standard?
It would give me 7.4v and around 7Ah which seems like aprox. 2 hrs of charge (7x7.2)/(20W)*.8 with .8 being my accounting for non-perfect discharge/charge conditions and battery imperfection. Is the 7.4v required for running a Wii board? or could I get away with 1s2p?

I have batteries picked out:THESE

and a CMB, but I'm concerned on this one..., as it requires a 9-15V in for charging. I'm wanting to be able to charge off of my same power adptr as my Cellphone (USB-C 5v 2a) so I'm wondering what if any solutions the community has come up with to push a charge to a 7000mAh bank? I noted the all-in-one power management boards on the bitbuild store, but that's fairly costly given the alternatives in the wild. Not to mention I'm in no shortage of components to draft up my own PCB, just not the most skilled with power electronics

The trim allows you to use custom regulators so that you can use a < 12V input, and of course that will slightly improve efficiency but for a 6 layer board you can still expect around a 15-20W power draw.. It's best to just pick up a 4 layer since the Wii board itself is only around 10 dollars if you look in the right places, and there are methods to select 4 layer boards without looking at them.

If you want to use USB C, you can either make a breakout board which just has the port and a 5.1k pulldown resistor on each CC pin (I'm sure these exist already somewhere too). Of course that limits you to 15W max to charge which is not great. In addition your charging circuit would need to support 5v as you mentioned. I would suggest you use the USB C board alongside the Wii PMS from the bitbuilt store which is an all in 1 solution to regulators and battery management. The USB C board with the PMS natively supports USB C PD to charge at much higher wattages.

Also, there's no need to post the same thing in 2 different threads.

 

[medic3k]

I would suggest you use the USB C board alongside the Wii PMS from the bitbuilt store which is an all in 1 solution to regulators and battery management. The USB C board with the PMS natively supports USB C PD to charge at much higher.

yikes! the cost for those two boards together is around $120USD.. thats almost twice what the entire rest of the project has cost me. ill stick with the red CMB i linked and a 12v wall-DC power supply, it may not be as convinient for portability (haul extra charger around) but its only going to cost $11 vs $120.

Aside from charging circuitry im curious how my battery choice will work. it would be 7.4v 7000mAh if i did 2S2P, but im conceened about how "legal" this is for airplanes. is there an upper mAh limit per-cell when traveling by plane? my main use for this portable is my frequent travel between US and Korea for work. geting it confiscated by TSA is not an ideal

also sorry for double post, i realized my initial post was in wrong thread when i discovered this

 

[GingerOfOz]

You should be fine with that battery setup on planes. I've brought a portable on a plane with that exact charging/battery setup and haven't had issues. Nobody has had a portable confiscated in quite recent memory, so as long as your build looks like a video game console at a glance you should be fine.

 

[medic3k]

Great. I also ended up finally finding the exact U.S. Rules in case anyone is interested:
https://www.faa.gov/hazmat/packsafe/more_info/?hazmat=7
it looks like 100Wh per-cell and it really only seems to be enforced on loose batteries and objects with large battery packs

Also for any curious who are too lazy to look it up, the restrictions are:

<100Wh per cell, with solder/spot-welded batteries being viewed as single-cell.
IE if the 2 cells are rated as 3.7v 3500mAh and welded in series they are viewed as a single
7.4v 3500mAh cell, but if they are not permanently combined (ie in battery holder which then "series-connects" them) they are viewed as two individual 3.7v 3500mAh cells

having 2s2p is easily in tolerance as its 7.4V 7Ah (7*7.4=51.8) so you could actually carry a spare 'battery-pack' and be fine lol

As reference a 12v battery is 96Wh, so any portable's power source is going to be easily justified unless you've got a soldered/welded cell cluster with more then 2s4p of my batteries (103.6Wh)

 

[kpacardo]

Is the Adafruit Powerboost 1000C considered a CMB?

I want to use the green panasonic li-ion 18650 cells. Is this CMB from the BOM still recommended (https://www.ebay.com/itm/Intelligent...2S-Packs-18650-lithium-Satellite/311721987212) or should I be using the powerboost for my power supply needs?

 

[SuleMaker]

Ok thanks, that makes sense. This photo is what you mean?

With this board could you hot plug the DC jack without console reboots?

 

[The Craftman]

Hello, I'm very new to portabilizing and have a few questions about batteries.
I've read over the Portables and Batteries: A Guide and Explanation post many times, and was considering using the 2s CMB recommended (https://www.ebay.com/itm/311721987212) for my raspberry pi 3B+ portable. Though I had some questions on things like, can I attach an on/off switch to it, how exactly do I connect the batteries to it, is there a specific charge port I should use or can I just use say a USB-C port. This will be my first ever portable, so I'm not sure about a lot of things. Any help would be nice.

 

[Wesk]

Hello, I'm very new to portabilizing and have a few questions about batteries.
I've read over the Portables and Batteries: A Guide and Explanation post many times, and was considering using the 2s CMB recommended (https://www.ebay.com/itm/311721987212) for my raspberry pi 3B+ portable. Though I had some questions on things like, can I attach an on/off switch to it, how exactly do I connect the batteries to it, is there a specific charge port I should use or can I just use say a USB-C port. This will be my first ever portable, so I'm not sure about a lot of things. Any help would be nice.

The Raspberry Pi is very simple to use with batteries as you can simply power them from all the parts found in a cheap battery bank. Using components like the ones you listed will only complicate a portable Pi build.