12.8 VDC 38120S battery pack for 100 Watt HAM radio?

[Rapidrob]

I've done a search here and not found what I need to know.
I'm going to use 8 ( eight each ) 38120S LiFePo4 batteries to build a portable battery pack for my HAM radio which I will be running at 100 watts ( 22 amp draw on transmit )
I can either use 2 ( two ) packs of four batteries each having a BCM and somehow tie the two together?
or one pack of eight wired to produce 14-16 VDC ( radio wants to see 13.8 VDC on transmit ) if that is possible?
I've not seen a BMS for running two battery packs together for one constant output of 12-16 volts. nor one for eight cells providing 12.8-16 VDC?
Some of the 18650 battery packs can have a BMS that jumps from one-to-another. Is there a BMS for 38120S batteries that will do that as well?
I would like to get fours hours of run time on the radio. Transmit every 30 seconds at 22 amps, and receive at 1.5 amps for 30 seconds.
I do not want to run QRP ( low power ) out of the radio.
I would appreciate any helpful info from you experts. I will in the future run a Solar cell charge device to help maintain battery current.
Thank you.

 

[sunshine_eggo]

I've done a search here and not found what I need to know.
I'm going to use 8 ( eight each ) 38120S LiFePo4 batteries to build a portable battery pack for my HAM radio which I will be running at 100 watts ( 22 amp draw on transmit )
I can either use 2 ( two ) packs of four batteries each having a BCM and somehow tie the two together?

Yep. Simply connect the main + and - of each battery to parallel them. Each would have a BMS.

BCM is typically used by automotive applications - more commonly referred to as BMS in the DIY world.

or one pack of eight wired to produce 14-16 VDC ( radio wants to see 13.8 VDC on transmit ) if that is possible?

2P4S = 4 groups of two cells in parallel, the 4 groups in series.

14-16VDC on LFP is a challenge. They behave like lead-acid in needing a higher voltage to charge and then they'll settle to and operate at about 13.4V.

I've not seen a BMS for running two battery packs together for one constant output of 12-16 volts. nor one for eight cells providing 12.8-16 VDC?

Again 16V isn't an option with LFP. Maximum practical is 14.6V, 14.4V preferred.

There are BMSs as you describe, but they'll completely blow away your budget for this project. Easier to just get two inexpensive BMS - one for each battery.

Some of the 18650 battery packs can have a BMS that jumps from one-to-another. Is there a BMS for 38120S batteries that will do that as well?
I would like to get fours hours of run time on the radio. Transmit every 30 seconds at 22 amps, and receive at 1.5 amps for 30 seconds.

For every hour, you would need 0.5 * 22A + 0.5 * 1.5A = 11.75Ah

A 50Ah battery should get you there with a little margin.

 

[Rapidrob]

Thank you Sunshine_Eggo.
I will check out 2P4S packs.

 

[Rapidrob]

I've ordered the batteries for 2P4S packs and now need to order a LiFePo4 charger. I would like to have a low amp adjustable type to increase the life of the batteries as well as to be able to adjust the charge voltage. Preferably one that will plug into the BMS. ( I have not ordered the BMS as yet until I find a charger that will plug into it. )
Which charger would you recommend to use?
Thanks for your recommendations.

 

[Rapidrob]

I just found the "holders" for the 38120 batteries are no longer in great supply on the internet and the two places that had them wanted 25-35 dollars to ship one pound of them ( 16 ) !
I was born at night but not last night.
If anyone has 8 or 16 of the holders they want to get rid off, please let me know.