Pre-Build, Portable Pack - 12v LiFePO4

[balikbayan21]

Hey all, I'd like to build a battery that I can use for camping. I'm interested in input please.

I'd like to be able to charge it with a standard 110v outlet (or laptop input)
I'd also like the option of charging with a solar panel (havent figured that out either)

I was looking at the

• 100Ah LiitoKala AliExpress LiFePO4 cells ~$159
• 100A DALY bms w/ bluetooth ~$66
• voltage meter for box (presumably I'd like to have the cells in a box with visible capacity) ~$4

I haven't figured out the inverter, but I'm guessing I need something that plugs into the main battery negative and then the BMS positive... I figure with 12v100ah I've got just over 1KWh assuming the stars align, so a 300w inverter with a 110v AC outlet and a pair of USB ports would be handy. Any suggestions on this piece would be much appreciated.

I haven't figured out a charging method for solar and/or AC power. I don't have any solar panels in mind, so initially it's gonna be just AC input. Do you guys recommend using a laptop charger, or is there something else you use?

I'll likely assemble the unit then worry about the box last.

Thank you for reading.

 

[Ceberha]

Because of the flat charge/discharge curve for LFP cells a simple voltage meter will not work well for capacity - you will need something like this from AiLi (Battery Monitor Voltmeter Ammeter Voltage Current Meter 8-80V 0-100A)

AiLi Battery Monitor Voltmeter Ammeter Voltage Current Meter 8-80V 0-100A Auto Car Motor Boat Caravan RV Motorhome - - Amazon.com

AiLi Battery Monitor Voltmeter Ammeter Voltage Current Meter 8-80V 0-100A Auto Car Motor Boat Caravan RV Motorhome - - Amazon.com

www.amazon.com

A laptop charger will not have an appropriate profile for LFP. I go a cheap CC/CV dedicated LFP charger for my portable pack from AliX, but do not have a link. To charge from solar you will need a charge controller. For my portable box I used this rather PWM inexpensive one, which works fine for charging with 2 or 3 100W panels in parallel. It has a built-in profile for lithium batteries.

https://www.amazon.com/gp/product/B07G1PL1B9/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

 

[balikbayan21]

Okay, so I've revised this a bit, how about this for charging the battery?

I figure the BMS has bluetooth, so I'll just monitor capacity that way.

...is it just me, or does battery building appear very expensive?