I have a 10kva multiplus 2 with 7 bluenova batteries in parallel.The last 2 batteries which i bought does'nt seem to charge at the same rate as the other 5.EG The 5 will have SOC of 78,79.80,78,77 but the other 2 will be 30,32.I have tried everthing As I even change my inverter .So please help