Constraint on component store

[DR Mohammed Riadh Habour]

Hi everybody 

I would like to set up a constraint for battery store, to make the minimum of SOC at least 20% of maximum of SOC over all snapshots, here is both of battery subsystem and constraint :

Battery subsystem : 

IES.add("Bus","IE_battery")
IES.add("Store","IE_battery_storage",bus = "IE_battery", e_nom_extendable  = True,
e_cyclic    = True, marginal_cost = Battery_marginal_cost, capital_cost = Battery_capital_cost)

IES.add("Link","IE_battery_charger",bus0= "IE_electricity_system",bus1= "IE_battery",
p_nom_extendable= True, efficiency = Inverter_efficiency,)

IES.add("Link","IE_battery_inverter", bus0 = "IE_battery", bus1= "IE_electricity_system",
p_nom_extendable = True, efficiency= Inverter_efficiency, marginal_cost  = Inverter_marginal_cost, capital_cost = Inverter_capital_cost)

Constraint 

e_stores           = lpmodel.variables['Store-e']
IE_battery_storage_e      = e_stores.loc[:,'IE_battery_storage']  
IE_battery_storage_e_min  = IE_battery_storage_e.groupby(min) 
IE_battery_storage_e_max  = IE_battery_storage_e.groupby(max) 

lpmodel.add_constraints((IE_battery_storage_e_max * 0.2) <= IE_battery_storage_e_min, name='IE_batt')  

However  I got the next error 

--------------------------------------------------------------------------- TypeError Traceback (most recent call last) Cell In[59], line 6 4 IE_battery_storage_e_max = IE_battery_storage_e.groupby(max) #("snapshot") 5 #lpmodel.variables['Store-e'].loc[:,'IE_battery_storage'] ----> 6 lpmodel.add_constraints((IE_battery_storage_e_max * 0.2) <= IE_battery_storage_e_min, name='IE_batt') TypeError: unsupported operand type(s) for *: 'LinearExpressionGroupby' and 'float'

Any support to solve the error is more then welcome.

[DR Mohammed Riadh Habour]

Could someone assist or provide guidance regarding a question I have about the minimum and maximum battery  charge ? Thank you