Hello Preben,  

Thanks a lot for your comments

I resolved all the errors as pointed out by you. Issue with "indets(BatSys,name)" (returning R[pN] and RpP] along with x and t), I think its because of some miss-specification of squares of R[pN] and R[pP] terms in equation NegativePDE2 and PositivePPDE2  respectively. When I deleted those terms and rewote, it fixed the issue! Now, indets(BatSys, name); is returning {t, x} 

I checked all the equations with lprint() and they look ok to me.

But, still it is throwing the same error(Highlited in blod below). Attached is the updated version of the file. BatteryPDEEquationsB.mw

>pds := pdsolve(BatSys, IBC, numeric, variables, time = t, range = 0 .. L[N]+L[sep]+L[P]);
Error, (in pdsolve/indexlex) invalid input: a string/name list is expected for sort method `string`

Thanks a ton for all the support and help you have been providing. 

Kind Regards,

Vinay

Hello Preben,  

Thanks a lot for your comments

I resolved all the errors as pointed out by you. Issue with "indets(BatSys,name)" (returning R[pN] and RpP] along with x and t), I think its because of some miss-specification of squares of R[pN] and R[pP] terms in equation NegativePDE2 and PositivePPDE2  respectively. When I deleted those terms and rewote, it fixed the issue! Now, indets(BatSys, name); is returning {t, x} 

I checked all the equations with lprint() and they look ok to me.

But, still it is throwing the same error(Highlited in blod below). Attached is the updated version of the file. BatteryPDEEquationsB.mw

>pds := pdsolve(BatSys, IBC, numeric, variables, time = t, range = 0 .. L[N]+L[sep]+L[P]);
Error, (in pdsolve/indexlex) invalid input: a string/name list is expected for sort method `string`

Thanks a ton for all the support and help you have been providing. 

Kind Regards,

Vinay

Missing attachment in previous post is attached in this post. Below is the link to attachment:

BatteryPDEEquationsB.mw

Thank you,

Kind Regards,

Vinay