Thank you for bringing your concern to our attention via the community.
Referring the PowerCore 26800, I believe you are asking about the PowerCore+26800 PD. We regret to inform you that we only recommend charging the MacBook Pro USB-C devices with our PowerCore+26800 PD battery. The MacBook Pro 2013 version has a MagSafe 2 connector which will not be fit with the Type-C PD port on the battery.
If you need additional assistance, please email to firstname.lastname@example.org.