Trying to build is a Lithium Ion Battery

[CavemanNeil]

Hello and thank you for reading our post, what we are trying to achieve is a Lithium Ion Battery that will operate at least 8 to 16 hours of use, with a preferred weight is half a lb or Less per battery. We are trying to create a reliable LI battery that is easily charged by both solar power and or wall charging either indoors or outdoors for backpack purposes so as not to be limited by weight or capacity. Any guidance on configuration, pitfalls and potential hazards is welcome. Here is what we have learned so far that in order to build the power pack from the inside out to the completed, usable product we will require: IE from the battery cells to the PCB to the power cable to the barrel plug, please keep in mind we are not experts this is a home created item to fit our needs. We are looking for advice on creation or possible schematic design. Question, if you know of a source of supply that will meet our needs would you recommend we purchase the battery pack or rather build the battery pack? What are the advantages to either scenario?

What we are trying to build is a Lithium Ion Battery for a device that’s design parameters are rated for the following sources:

PSA2 (Wall Unit Charger w/ Interchangeable International Plugs)
BAT4 (8 Hour Battery Pack) 4SP1
BAT8 (16 Hour Battery Pack) 4SP2

The existing Lithium ion Battery Unit in use is a:
BAT8
14.4V, 5200mAH, 75Wh
Configuration 4SP2
With what we think is a EIAJ-05 or a J5BP5 barrel plug that goes from the battery to the device specification can be provided as soon as we can acquire a caliper
The Wall Plug in Current Use is a :
PSA2
Input: 100-240V
50-60Hz, 1.0A
Output: +18V---, 1.67A

The components we must specify, if we are to fabricate, are:

Male Barrel Plug (From Device to Battery Pack)
Wire that goes from plug to Core question what kind of wire would you recommend? Or how do I gauge the existing wire?
PCB & Charge Indicator Light On the Housing
LI core that is configured in a 4SP2 w/ UL parameters of 14.4V, at least 5200 mAH (What might happen if we up the mAH?)
Female Barrel Plug in the Housing(to accommodate wall or Solar Panel charger)
Housing to Accommodate Everything
We are considering a EarthTech R14 (14W) as a solar source in the field. Our existing wall plugs should be fine for locations where electricity is available.

 

[amberwolf]

Lithium Ion Battery that will operate at least 8 to 16 hours of use, with a preferred weight is half a lb or Less per battery.

How long does your existing battery last, and how much does it weigh?

To find out if it is possible to do what you want, you can use that to create a ratio, to then multiply with your needed operating time, to see what the new one might weigh.

We are trying to create a reliable LI battery that is easily charged by both solar power and or wall charging either indoors or outdoors for backpack purposes so as not to be limited by weight or capacity. Any guidance on configuration, pitfalls and potential hazards is welcome.

There's a lot of "solar charging" threads that should help you see what panels, chargers, and other options you have for that part, if you poke around the forums. Search for "solar" by topic title and display by topic.

BAT4 (8 Hour Battery Pack) 4SP1
BAT8 (16 Hour Battery Pack) 4SP2

Does that mean that it is 4 cells in series, and either just one string, or 2 parallel strings? If so, that is normally written 4s1p or 4s2p; that might help you understand more of the various pack build threads around here (that have a lot of info on how to physically build your own packs).

BAT8
14.4V, 5200mAH, 75Wh
Configuration 4SP2

And does this pack (or did it when new) last the 16 hours I presume the "8" is meant to signify?

LI core that is configured in a 4SP2 w/ UL parameters

If you build it yourself, it will not have any UL parameters, as that is a listing you must do specific testing to apply for, thru Underwriter's Laboratories.

of 14.4V, at least 5200 mAH (What might happen if we up the mAH?)

You get a pack that is larger (and heavier) by adding more parallel strings of cells, but it lasts longer by however many more mAh it has.

We are considering a EarthTech R14 (14W) as a solar source in the field.

If that means it is a 14watt panel, what voltage would that be at? If it is at sufficient voltage to run your AC-wallpowered charger, it simplifies things. If it is only a 12v panel, you'll need to run a converter of some kind either to your pack voltage directly, or to wall-voltage to run your charger.

Either way it will likely take quite some time to charge your pack.

If your pack is 75Wh, then you would need to charge it at a rate of 75W for one hour to get that back. There are conversion losses from panel voltage to pack voltage, as well as panel losses from many things, so even if you use a 75W rated panel set it will probably not supply enough power to charge a 75Wh pack in an hour.

And even a 50w panel, from what I've seen, is not usually what I'd call easily man-portable.

I'd definitely recommend looking around at the various solar charging threads as noted above, to get an idea of what you need for that.

 

[dogman dan]

Look into "12v lithium jump starting packs" They are exactly what you are looking for, and you can find them all over the place now.

Usually they are about 120 watt hours. (12v x 10 ah if you believe the specs) If the run time for your devices is too short, then the solution is two of them. One would run a set of 12v Led lights for a good long time,, and also charge stuff like your phone.

Rechargable with a fairly small panel, like 25 w 12v solar panel. 5 hours or so in the sun,, 100 watt hours.

For example, here is an 8 ah they say,, at 1.3 pounds.

https://www.lowes.com/pd/Schumacher-Electric-400-Amp-Car-Battery-Jump-Starter/50437772?cm_mmc=SCE_BINGPLA_ONLY-_-ToolsAndHardware-_-SosTrailerRampsAndTowing-_-50437772:Schumacher_Electric&CAWELAID=&kpid=50437772&CAGPSPN=pla{ifdyn:dyn}&k_clickID=1332e22e-313e-495d-a52c-facee1440130



Or similarly, a 12v power drill pack,, ready built, just what you need,, but they are usually smaller, about 2 ah.

For a larger capacity cheaper,, then you might look into RC drone battery packs. 4s 5 ah is cheap, but of course, you still will only get but so much daily watt hours from a small solar panel.

 

[CavemanNeil]

Thank you so much for the feedback. I am studying all your suggestions and will formulate more questions.

 

[Hillhater]

You need to know what the power draw (mA load, etc) constant and Maximum, is going to be to estimate pack capacity.
But, it Sounds like you are looking for a Laptop portable back up power supply battery ?
Have you looked for commercial units, Ebay, etc ?