Dead battery in Sardinia — EFB vs AGM replacement & DIY registration (Superb Mk3)

Hey,

My car died after being parked for 48 hours while I'm on holiday in Sardinia, far from any city or car mechanic.

I would really appreciate some help confirming the correct replacement battery and the steps needed to install and register it myself.

Car details

Model: Škoda Superb III Combi (2022), L&K

Engine: 2.0 TSI, 272 HP, 4×4

VIN: TMBLE9NP9N7011795

Start-Stop: Yes

Current battery (factory-installed):

• Manufacturer: Exide (Made in Poland)

• Škoda/VW part number: 5TA 915 105 B

• BEM code on sticker: 5TA915105B

• Battery identification / serial: TU1A10722M03W

• Technology: EFB+

• Capacity: 70 Ah

• Starting current: 700 A (EN/SAE/GS) / 420 A (DIN)

• Voltage: 12 V

Plan of action

I'm considering two replacement options plus diagnostic tool.

Battery

Option 1 - Varta Dynamic EFB N70 (570500076K262)

This seems to be the closest replacement for my original Exide EFB+.

• 12 V, 70 Ah

• 760 A (EN)

• EFB technology

Since the technology and capacity are unchanged, I'm hoping the car will work immediately after installation, even without registration.

However, I'll still purchase a diagnostic adapter. I don't want to wait for battery delivery, discover that registration is necessary, and then lose another week waiting for a diagnostic tool.

I'd register the battery regardless, but having it work without immediate registration would be reassuring.

Option 2 - Varta Dynamic AGM A7 (570901076K262)

This would be an upgrade from EFB to AGM.

• 12 V, 70 Ah

• 760 A (EN)

• AGM technology

My understanding is that AGM offers better charge/discharge cycle durability and charge acceptance, particularly during short journeys and frequent Start-Stop operation.

Since this changes the battery technology from EFB to AGM, I understand that the BMS must be configured accordingly.

If the diagnostic tool can reliably handle the full registration procedure, and it's relatively straightforward, I'm leaning toward this option.

Diagnostic tool

I'm planning to purchase a Carista EVO with a Carista Pro subscription to register the replacement battery immediately after installation.

From what I've read, Carista supports battery registration on the Superb III, but I'd appreciate confirmation from anyone who has actually used it, particularly for changing from EFB to AGM.

I'm also open to other diagnostic tools if there's something more reliable, cheaper, or better suited to this task. I have a MacBook, a Windows laptop, and iPhones with me, so I'm fairly flexible regarding software and hardware.

I should also mention that I don't normally work on my car myself, so this is fairly new territory for me. If I'm overlooking something obvious, please let me know.

Thanks, Konrad