Exide EK151 Auxiliar · Auxiliary battery 15Ah 200A AGM

Yes. AGM (Absorbent Glass Mat) technology, 15 Ah and 12 V: sealed lead-acid, with the electrolyte held in glass fibre. It tolerates heat better and handles more cycles than a conventional battery, which is why it is the required technology with advanced Start-Stop and regenerative braking.

Yes. It is a AGM battery of 15 Ah, designed for vehicles with Start-Stop. AGM batteries support advanced Start-Stop and regenerative braking thanks to their higher cycle count. Once fitted it is ready to go; registering it via OBD, advisable on most modern models, lets the alternator charge with the optimum profile. As a rule: EFB for basic Start-Stop, AGM when there is also regenerative braking (more cycles); in any case, what the car manufacturer specifies.

Estimated lifespan of the Exide EK151: 5 to 8 years in mild-climate car use with Start-Stop. Treat it as an approximate guide, as every case is different. Many factors play a part: how it is used (lots of short trips, for example), temperature (cold makes every start harder and intense heat evaporates the electrolyte), the condition of the alternator and charging system, power drawn with the engine off and maintenance, as well as the type of car and whether it has Start-Stop.

Check the room available in your car, because a single millimetre too much can stop the clamp from closing. Its dimensions are 150×90×145 mm, also written 150x90x145 mm; the height already includes the terminals.

The EK151 has the positive on the left: that is its polarity. Face the battery with its terminals nearest you and see which side the positive post (+, red ring) is on. A change of polarity from the original means longer cables or a reconfigured system and can cause a short circuit: check it before ordering.

For your own vehicle: type your number plate into the finder (DGT/DVLA/KBA identify model and engine), check the "Compatible vehicles" tab below, listing vehicles verified by our technical team, or message us on WhatsApp with make, model, engine and year; we reply during business hours (Mon–Fri 10:00–13:30 and 16:30–18:00 (Spanish time, CET)). Always cross-check with what the car manufacturer states in the owner's handbook.

Interchangeable means the same dimensions, same polarity, same Ah and same CCA; for the EK151, 15 Ah (200 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 case and same fitting as the EK151, from Tudor. Compared with the EK151 it has the same Ah and cranking power. It costs 10,35 € more. If you want to save or the EK151 is out of stock, it is the safe alternative: same dimensions, same polarity and official warranty.

The Exide EK151 has a capacity of 15 Ah. In an AGM (Absorbent Glass Mat) battery the electrolyte is held in a glass-fibre mat: no spills, and many more charge/discharge cycles than a conventional battery. For regenerative braking systems such as BMW EfficientDynamics, Mercedes Eco, Audi MHEV, Land Rover ECO or Volvo i-Stop, AGM is the recommendation; it also copes better than an EFB with tilting, vibration and extreme temperatures.

It is not strictly necessary on most cars, because the alternator detects the change and adapts the charge. The advisable step is to register it via OBD: the charging profile is optimum from the first minute and the battery lasts longer, especially on brands with sophisticated BMS (BMW, Mercedes, Audi, Volvo, Land Rover). Without registration there is no starting problem: the alternator adjusts the profile within a few days. Any garage with an OBD scanner can do it in a few minutes. If you prefer to do it yourself: VCDS / Carista (VAG), Bimmercode (BMW) or iCarsoft.