I'll try and be succinct here; any thoughts or ideas wil be greatly appreciated. I've been through the forums, talked to the Lhs and basically am asking for anyone's help/opinion on why my batteries are puffing. Possibly just flat out quality of battery? Here's my setup as it sits now.

Proboat MG29 V3
Leopard 4082 1800kv
Seaking 180 amp esc
Castle creations 6mm plugs
Cooling system is upgraded plenty.
Flex .187
442/3, x642, x445, x447, GR 4057/3- ran them all.
Reinforced hull/hatch, blue printed, blah blah.

I've gone through:
2 sets of electron pro 5200mah 50c- one puffed up and read 155 degrees Fahrenheit. The exact battery on the other side was reading 104 degrees.

Same with the set of SPC 5600mah 60c. One is fine on temps and no puffing. The other was 150+ external temp and just now was worried it would pop when I pulled it out of the boat. I do not believe this to be a connection problem. All plugs, motor, esc have not gone above 115f. Just one battery in each of my sets and have been on both sides of the wiring harness.

This is my very first Rc boat. Never had one until November When i bought this one and basically upgraded as ive learned along the way. I learn quickly and know how to fiddle fart in the shop. Maybe I'm missing something here. Please help guide me as to how I may keep her fast and not buy batts every 5-6 runs boating.

Thank you Sirs,