Varta H15 Dynamic AGM · Start-Stop battery 105Ah 950A

Yes. AGM (Absorbent Glass Mat) technology, 105 Ah and 12 V: sealed lead-acid, with the electrolyte held in glass fibre. It is the technology required by cars with advanced Start-Stop and regenerative braking. It withstands more cycles than a conventional battery and copes better with heat.

AGM batteries support advanced Start-Stop and regenerative braking thanks to their higher cycle count. The Varta H15 is AGM, so yes, it is designed for Start-Stop cars. It needs nothing to work, though on most modern cars registering it via OBD is advisable so the alternator adjusts its charging profile. The general recommendation is EFB for basic Start-Stop and AGM where there is regenerative braking (it handles more cycles), unless the car manufacturer says otherwise.

Start-Stop or BMS specifics: do not remove the IBS sensor on the negative terminal (just loosen the cable nut); after the swap, register the battery via OBD so the alternator charges with the right profile; and never step down in technology: if the car had AGM or EFB, the new one must be the same or better, as a conventional battery lasts only a few months. Allow 15-30 minutes and a 10 mm spanner for a L6 case like this one. If the car keeps its battery in the boot or under a seat, it can take up to twice as long. Steps: 1) switch off and remove the key; 2) find the battery (bonnet, boot or under a seat); 3) undo the negative (−), then the positive (+); 4) remove the clamp and the old battery; 5) fit the new one facing the same way (positive on the right) to match the polarity; 6) connect the positive (+) and finally the negative (−). Our blog guide covers it in detail; if the owner's handbook describes a different procedure, follow the manufacturer.

As a rough estimate, the Varta H15 typically lasts 5 to 8 years in mild-climate car use with Start-Stop; it is a guide figure, not a guaranteed period. It can vary considerably with usage (short or long journeys), temperature, the condition of the alternator and charging system, power drawn with the engine off and maintenance, plus the car itself and Start-Stop. Cold demands more at every start and intense heat evaporates the electrolyte.

Before buying, measure the space in your car: one extra millimetre can stop the hold-down clamp from closing. The Varta H15 takes up 393×175×190 mm (length, width and height, terminals included), the European L6 case size, with a B13 hold-down.

Polarity of the Varta H15: positive on the right. It must match your current battery: reversed polarity means lengthening cables or reconfiguring the system, with a risk of short circuit. Seen from the front, terminals towards you, the positive (+) is the post with the red ring.

The H15 typically fits a wide range of European vehicles thanks to its standard DIN case format. Not sure? Try your number plate in the finder (DGT/DVLA/KBA detect model and engine) or the "Compatible vehicles" tab, checked by our technical team; if your car is not there, send us make, model, engine and year on WhatsApp and we will reply during business hours (Mon–Fri 10:00–13:30 and 16:30–18:00 (Spanish time, CET)). The car manufacturer's specifications always take priority over our tables.

Interchangeable means the same dimensions, same polarity, same Ah and same CCA; for the H15, 105 Ah (950 A cranking). Technology matters too: in Start-Stop cars, an EFB cannot be replaced with a conventional battery. The options at the same level are in the "Equivalents" section of this page.

Same range and the same performance as the H15. Compared with the H15 it has the same Ah and cranking power. It costs 54,60 € more. Either one works; decide by price.

Hence it is recommended for advanced Start-Stop with regenerative braking, such as BMW EfficientDynamics, Mercedes Eco, Audi MHEV, Land Rover ECO or Volvo i-Stop, and it handles tilting, vibration and extreme temperatures better than an EFB. The absorbent glass-fibre mat of an AGM retains the electrolyte, so it cannot leak and withstands considerably more cycles than a conventional battery. The Varta H15 has a capacity of 105 Ah.

Advisable, yes; essential, on most cars, no. Registering it via OBD makes the alternator charge with the optimum profile from the first minute and extends battery life, which matters most on brands with sophisticated BMS such as BMW, Mercedes, Audi, Volvo or Land Rover. A workshop only needs an OBD scanner and a few minutes. DIY apps: VCDS / Carista (VAG), Bimmercode (BMW), iCarsoft. If you do not register the H15, it will keep starting fine while the alternator adjusts the profile over a few days.