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Failed to find consistent initial values on lithium ion battery simulation

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Wencheng Li

Wencheng Li

February 27, 2010 4:48am UTC

Failed to find consistent initial values on lithium ion battery simulation

I was trying to simulate a lithium ion battery problem with COMSOL 3.2a, trying to see the same effect presented in the following reference:

Premanand Ramadass, Capacity Fade Analysis of Commercial Li-ion Batteries[D], USA: University of South Carolina, 2003.

In my modified model, when the simulation starts it reports

Error:
Time 0:
Failed to find consistent initial values.
Power_of_negative
Function: power
Failed_to_evaluate_expression
Expression: diff(((+(ep*sigma*phi1x)*test(phi1x)+(ap*kp*(c1maxp-theta*c1maxp)^alpha*(theta*c1maxp)^alpha*c2^alpha*(exp(alpha*F*eta/R/T)-exp(-alpha*F*eta/F/T)))*test(phi1)-0)*dvol),phi1_test)

Last time step is not converged.

I am a new user, don't know how to do this problem

Thanks.
Wencheng Li.

Attachments:   Li_battery_model.mph  

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Wencheng Li

Wencheng Li

February 28, 2010 8:10am UTC in response to Wencheng Li

Re: Failed to find consistent initial values on lithium ion battery simulation

hello,

The error, Failed to find consistent initial values, has been dispeared by modifying boundary conditions.

But 'error in residual computation' arose. maybe I need to fit the value of parameters.

The error, Last time step is not converged, is still there.

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Yannick Protière

Yannick Protière

March 16, 2010 8:30pm UTC in response to Wencheng Li

Re: Failed to find consistent initial values on lithium ion battery simulation

Hello,

I am experimenting similar issues.
My error message is following.

Did you solve your previous issue? If so, I could be interested how you did.

I am also a new user, an advice would be more than welcome.
Don't hesitate to contact me if you need additional informations, thanks in advance.

Yannick

Error:
Time 1935360:
Error in residual computation.
Power_of_negative
Function: ^
Failed_to_evaluate_variable
Variable: dwdH, Defined_as: ((-((c^(delta-1))*(phi*(phi*(delta*beta)))))/((1+((phi*beta)*((c^delta)-1)))^2))
Failed_to_evaluate_variable
Variable: Dts_c_di, Defined_as: dwdH
Failed_to_evaluate_expression
Expression: d(((-D_c_di*cx*test(cx))-(Dts_c_di*ct*test(c)))*(dvol),{test@1})
Last time step is not converged.

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Alexander Warning

Alexander Warning

June 2, 2010 3:12pm UTC in response to Yannick Protière

Re: Failed to find consistent initial values on lithium ion battery simulation

Hi,

I am a new user and having the same problem. If i refine my mesh the error takes longer to appear. I am not sure what this means except it is an error in convergence since my value being raised to the exponent should never be negative. I am assuming that if you put a logical statement somewhere to prevent this it should be cured.

Thanks
Alex

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Rajeswaran Radhakrishnan

Rajeswaran Radhakrishnan

April 19, 2011 4:02pm UTC in response to Alexander Warning

Re: Failed to find consistent initial values on lithium ion battery simulation

Hi,
I am a new user.I am also having the same problem,If u resolved the problem before,please help me to get right...

My error code is

Time 3.746334577378822:
Error in residual computation.
Power_of_negative
Function: ^
Failed_to_evaluate_variable
Variable: i0, Defined_as: (((k_pos*((c1max_pos-c1s_pos)^aA_pos))*(c1s_pos^aC_pos))*(c2^aA_pos))
Failed_to_evaluate_variable
Variable: i_loc, Defined_as: ((exp((((Far*aA_pos)*eta)/(Rg*T)))-exp(((((-aC_pos)*Far)*eta)/(Rg*T))))*i0)
Failed_to_evaluate_expression
Expression: d(((-K1eff*phi1x*test(phi1x)/L_pos-i_loc*Sa_pos*L_pos*test(phi1))-(0))*(dvol),{test@1})
Last time step is not converged.

Thanks,
Rajesh

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