Exide EK800 · Start-Stop battery 80Ah 800A AGM

Yes: the EK820 from Exide uses AGM (Absorbent Glass Mat) technology, a sealed lead-acid battery whose electrolyte soaks a glass-fibre mat. Compared with a conventional battery it withstands more charge/discharge cycles and handles heat better; it is the required technology for cars with advanced Start-Stop and regenerative braking.

Yes: being AGM, the Exide EK820 is designed for Start-Stop cars. AGM batteries support advanced Start-Stop and regenerative braking thanks to their higher cycle count. If the car recovers energy when braking, AGM is recommended for its higher cycle count; for basic Start-Stop, EFB. The manufacturer's specification comes first. It works once fitted; on most modern cars, registering it via OBD is advisable so the alternator applies the optimum charging profile.

Allow 15-30 minutes and a 10 mm spanner for a L4 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. If the car has Start-Stop or BMS: a) the technology must match the original (AGM or EFB) or be higher, because a conventional battery would fail within months; b) undo the negative cable at its nut, leaving the IBS sensor in place; c) it is advisable to register the battery via OBD so the alternator applies the proper charging profile. What matters most is the terminal order: removing, negative (−) before positive (+); refitting, positive (+) before negative (−). In between, with the engine off and the key out, release the clamp and fit the new battery the same way round as the original, positive on the right (polarity). Before you start, check the car handbook: the manufacturer's procedure always comes first. Our full step-by-step guide is on the blog.

As a guide, you can expect the Exide EK820 to last 5 to 8 years in mild-climate car use with Start-Stop, although the real figure may be higher or lower. What weighs most: temperature (cold makes starts harder and intense heat evaporates the electrolyte), frequent short trips, the condition of the alternator and charging system, power draw while parked and maintenance, not forgetting the type of car and Start-Stop.

Length × width × height: 315x175x190 mm (L4 case). Height is measured to the top of the terminals. Hold-down: B13. Measure your car's battery tray first; if the battery exceeds it by even a millimetre, the hold-down clamp may not close.

On the Exide EK820, the polarity is positive on the right. To check, stand the battery in front of you with the terminals nearest you: the positive (+) is the one with the red ring. Compare it with the battery you are replacing: if it does not match, cables must be lengthened or the system reconfigured, with a risk of short circuit.

Three routes: the "Compatible vehicles" tab on this page, with the vehicles verified by our technical team; your number plate in the finder, from which DGT/DVLA/KBA detect model and engine; and WhatsApp, with make, model, engine and year, during business hours (Mon–Fri 10:00–13:30 and 16:30–18:00 (Spanish time, CET)). If our table and the car handbook disagree, go with what the manufacturer says.

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. To replace the Exide EK820 without modifications, the other battery must be identical in size (L4 case), polarity, Ah and CCA.

It has the same dimensions, voltage and technology as the EK800, although it is not a manufacturer-approved equivalent. Compared with the EK800 it has the same Ah and cranking power. It costs the same. Check the positive terminal side and the original capacity before ordering; otherwise it is a straight swap.

Same case and same technology as the EK800: an alternative by size, not an official equivalent. Compared with the EK800 it has 2 Ah less. It costs 41,25 € more. If the polarity matches and your car had a similar capacity, it works as a replacement; if in doubt, ask us with your model.

Many more charge/discharge cycles than a conventional battery and no leaks: that is what AGM technology brings, with the electrolyte absorbed in glass fibre. Compared with an EFB it resists tilted positions, heavy vibration and extreme temperatures better, and it is the recommended option where there is regenerative braking (BMW EfficientDynamics, Mercedes Eco, Audi MHEV, Land Rover ECO, Volvo i-Stop). This EK820 delivers 800 A cold cranking (EN).

The alternator detects the new battery and adapts the charge automatically, so on most cars it is not compulsory. Even so, it is advisable to register it via OBD so charging is optimum from the first minute and the battery lasts longer, particularly on BMW, Mercedes, Audi, Volvo or Land Rover, with more sophisticated BMS. Without registration the car starts normally; the alternator simply takes a few days to adjust the profile. Any workshop with an OBD scanner does it in a few minutes; DIY, with VCDS or Carista (VAG group), Bimmercode (BMW) or iCarsoft.