My system is comprised of the following:
(2) 12V 100W panels wired in parallel
Renogy Wanderer 30A Lithium Charge Controller
300W Pure Sine Wave Inverter
Battery pack is a DIY 12V battery. (4) 3.2V 90aH lithium ion phosphate batteries in series w/ BMS. Varicore cells from AliExpress.
The battery voltage drops significantly even under super small loads. Under no load the battery voltage reads 13.09V, but once I start pulling 10 watts the voltage drops to 12.4V and keeps dropping after a few minutes. (picture below is with load and without load). All 4 cells are perfectly balanced while not under load (and mostly balanced while under a small load).
I do NOT have this issue with my small 12V 16aH lithium Miady battery from Amazon.
Any suggestions would be appreciated. It is very strange that if I am pulling a load during sunlight the voltage will jump all over, and if a cloud comes overhead the voltage drops considerably into the 12.6V range (even under small load like 15 watts).
(2) 12V 100W panels wired in parallel
Renogy Wanderer 30A Lithium Charge Controller
300W Pure Sine Wave Inverter
Battery pack is a DIY 12V battery. (4) 3.2V 90aH lithium ion phosphate batteries in series w/ BMS. Varicore cells from AliExpress.
The battery voltage drops significantly even under super small loads. Under no load the battery voltage reads 13.09V, but once I start pulling 10 watts the voltage drops to 12.4V and keeps dropping after a few minutes. (picture below is with load and without load). All 4 cells are perfectly balanced while not under load (and mostly balanced while under a small load).
I do NOT have this issue with my small 12V 16aH lithium Miady battery from Amazon.
Any suggestions would be appreciated. It is very strange that if I am pulling a load during sunlight the voltage will jump all over, and if a cloud comes overhead the voltage drops considerably into the 12.6V range (even under small load like 15 watts).