# Start-Stop battery Fulmen FK820 12V 82Ah 800A AGM ![Start-Stop battery Fulmen FK820 12V 82Ah 800A AGM](https://baterias.com/3757-home_default/battery-fulmen-fk820-12v-82ah-800a.jpg) > Fulmen FK820 Start-Stop battery 12V 82Ah 800A AGM. Dimensions 315×175×190 mm, + terminal on the right. For Start-Stop vehicles. **Category:** [Car batteries equipped with start stop system](https://baterias.com/gb/car-batteries-equipped-with-start-stop-system) → [Fulmen](https://baterias.com/gb/fulmen) - **Canonical URL**: https://baterias.com/gb/battery-fulmen-fk820-12v-82ah-800a - **Language**: en-GB - **Brand**: Fulmen - **Reference**: BCOM-FULMEN-FK820 - **EAN**: 3661024047418 - **MPN**: FK820 - **Stock**: Out of stock ## Technical specifications | Feature | Value | |---|---| | Brand | FULMEN | | Reference | FK820 | | Model | FULMEN AGM | | Voltaje | 12 V | | Largo | 315 mm | | Ancho | 175 mm | | Alto | 190 mm | | Peso | 23.3 kg | | Tecnología | AGM | | EAN | 3661024047418 | | Scheme | Positive terminal on the right | | Terminal | 1 | | Subjection | B13 | | Arranque en frío CCA EN | 800 A | | Capacidad C20 (Ah) | 82 Ah (c20) | | Box Type | L04 | ## Quick description **Fulmen FK820 12V 82Ah 800A** is a dedicated Start-Stop battery with AGM/EFB technology. Withstands intensive cycling at traffic-light stops (hundreds of cranks per day), recharges quickly while driving and keeps comfort loads alive during long idle periods. ### Why this Start-Stop battery? - **Designed for Start-Stop** built for the intensive cycling of modern cars - **2 to 3 times longer life** vs fitting a cheap conventional battery - **Fast recovery** recharges in minutes once the engine is running 🔌 Voltage 12 V ⚡ Capacity 82 Ah C20 🔋 Cold cranking 800 A EN-1 📏 Dimensions 315×175×190 mm ⚙️ Technology AGM 🧭 Polarity Positivo a la derecha ⚖️ Weight 23,3 kg 🏷️ Model FULMEN AGM ## Description ## Battery Fulmen FK820 82Ah 800A 12V The Battery FULMEN FK820 82Ah 800A 12V AGM belongs to the Fulmen AGM batteries range. They are batteries with a greater load capacity to absorb the additional energy resulting from the recovery of braking energy and other intensive uses. Made with high performance components and materials, new generation AGM batteries also support other intelligent fuel savings. ### Ideal for: - Start-Stop vehicles - Microhíbrido vehicles - Teams that consume a lot of energy - SUV and vans - Large cars ### Battery advantages and characteristics FULMEN FK820 82Ah 800A 12V - Greater starter power - Greater resistance in cycles - Greater useful life - 4 times the capacity of a high heat battery - Vrla technology - Sealed battery - Original equipment and manufacture - It does not require maintenance - Installation within the vehicle cabin **Always remember to replace an AGM battery with another AGM battery** ### How to find the right battery for your vehicle? In recent years, there has been an increase of almost 300% in the energy needs of vehicles.To select the appropriate battery, it is essential to consider not only the power and displacement of the engine, but also the equipment, the climate and the usual driving style. The wide Fulmen battery range offers a complete and varied catalog to meet the electrical demands of any vehicle. From small and simple gasoline engines to large and robust industrial engines, Fulmen batteries guarantee a reliable and safe start. If you do not find the battery you need or have doubts about which battery, do not hesitate to contact us. The Battery FULMEN FK820 82Ah 800A 12V AGM has been designed by Fulmen with the highest peel standards Fulmen batteries guarantee a higher long -term performance and more useful life to your vehicles and devices Fulmen is a recognized battery brand, especially in the automotive sector.Fulmen is part of the Exide Technologies group, a leading company worldwide in the development and manufacture of lead-acid batteries and advanced energy storage technologies. ### Fulmen batteries, always an excellent option - Quality batteries - Greater shelf life - Great long -term performance - It has a catalog for a wide range of applications ### Before buying your Fulmen battery - **Understand your needs**: Determine the type of battery you need according to your vehicle or device.Consider the required capacity, voltage and size - **Investigate the available options**: Investigate different brands and types of batteries to find the one that best suits your needs and budget - **Check the specifications:**Be sure to carefully review the technical specifications of the battery, such as capacity, type of chemistry, dimensions and compatibility with your vehicle - **Terminals:**Check that the scheme and position of the terminal of your new battery are identical to the values of the old model If you want additional information about Battery Fulmen FK820, you can download the product's technical sheet at the following link: [ Download technical sheet Fulmen FK820 82Ah 800A 12V](/fichastecnicas/datasheet-battery-fulmen-fk820-82ah-800a-12v.pdf) ## Frequently asked questions ### Is the Fulmen FK820 an AGM battery and what are the benefits of AGM? Yes. The FK820 from Fulmen uses AGM (Absorbent Glass Mat) technology: a sealed lead-acid battery where the electrolyte is absorbed in a glass-fibre mat. It withstands more charge/discharge cycles than a conventional one, handles heat better and is the required technology for cars with advanced Start-Stop and regenerative braking. Expected lifespan: 5-8 years under normal conditions. ### Is the Fulmen FK820 battery suitable for Start-Stop? Yes. As AGM technology it is designed for Start-Stop vehicles. AGM batteries support advanced Start-Stop and regenerative braking thanks to their higher cycle count. EFB is recommended for basic Start-Stop; AGM is recommended when regenerative braking is also present, thanks to its higher cycle capability. It works straight out of the box — on most modern vehicles registering the battery via OBD is recommended so the alternator automatically applies the optimal charging profile. ### How do I check that the Fulmen FK820 battery fits my vehicle? Three ways: 1) enter your number plate in the finder (DGT/DVLA/KBA auto-detect your model and engine); 2) check the "Compatible vehicles" tab on this page, where we list every vehicle verified by our technical team for the FK820; 3) if you cannot find your model, message us on WhatsApp with brand, model, engine and year — we reply during business hours (Mon–Fri 9:00–18:00 CET). ### How is the Fulmen FK820 battery installed in the vehicle? In most cars it fits in 15-30 minutes with a 10 mm wrench; if the battery is under the seat or in the boot the time can double. See the step-by-step guide on this page. Quick summary: 1) switch off the engine and remove the key; 2) locate the original battery (engine bay, boot or under seat); 3) disconnect the negative (−) terminal first, then the positive (+); 4) loosen the hold-down clamp and remove the old battery; 5) fit the new one in the same orientation — match the polarity shown on the product sheet; 6) connect the positive (+) first, then the negative (−). On cars with Start-Stop or BMS, register the battery via OBD so the alternator applies the correct charging profile. ### How many years of warranty does the FK820 model cover? We provide 2 years of official manufacturer warranty against manufacturing defects. Coverage includes cell breakdowns, internal short-circuits and abnormal capacity decreases. It does NOT cover misuse (prolonged overcharging, inadequate charger, defective alternator). If the battery fails, we replace it at no cost after a technical inspection. ### When will I receive the FK820 model? In mainland Spain and Portugal it arrives in 24 h if you order before 17:00 and the battery is in stock — it leaves the same day and arrives the next business day. Afternoon or weekend orders ship the next business day. For Balearics, Canaries and other EU destinations, allow 2-5 days. Shipping cost is calculated in the cart based on destination and service (standard, express, cash on delivery). Tracking number is sent by email + SMS as soon as the parcel ships. ### How do I return the FK820 model if it doesn't fit? Yes. You have 14 days from delivery to return it. In mainland Spain and Portugal returns are FREE — we cover the return shipping cost via prepaid label. In other EU countries the return shipping cost is the customer's. It must arrive in its original packaging with no signs of installation. If it was defective, the warranty covers replacement even after the 14-day period. ### Where can I buy the Fulmen FK820 battery? At baterias.com — authorised distributor with real stock, 24h delivery in mainland Spain and Portugal if you order before 17:00, and full manufacturer warranty. Shipping cost is calculated in the cart based on destination and chosen service (standard, express, cash on delivery). Secure payment by card, Bizum, PayPal or bank transfer. If you choose at-home installation, our technician will take the used battery and dispose of it through an authorised collection point. ### What is the service life of the FK820 model? Expected lifespan of the Fulmen FK820 is 5 to 8 years in mild-climate car use with Start-Stop. In cold regions it drops slightly due to cold-start stress; in very hot regions it also drops because of electrolyte evaporation. To extend its life: avoid deep discharges (headlights on with engine off), have the alternator checked yearly, and keep the battery clean and properly secured. ### What are the dimensions of the Fulmen FK820 battery? Dimensions (length × width × height) are 315×175×190 mm — also written as 315x175x190 mm and correspond to the European L4 case size — following the European DIN standard. Always measure the space in your car before buying: even one extra millimetre can prevent the hold-down clamp from closing. The height shown includes the terminals. ### How much does the Fulmen FK820 battery weigh? It weighs 23,3 kg. Most of the weight is lead. If you plan to fit it yourself, use gloves and a carrying strap (AGM batteries are slightly heavier than conventional due to the absorbent glass-mat fibre). ### What is the capacity and CCA of the FK820 model? Nominal capacity 82 Ah[?cca: and [cold-cranking amps 800 A]] at 12 V. Ah measure the total energy available (autonomy); CCA (also written A in cold or EN under the European standard) measure the instantaneous power to crank the starter motor. A battery with more CCA starts better in winter; one with more Ah keeps accessories on for longer. ### Will the Fulmen FK820 battery fit my car? Three options to confirm: 1) enter your number plate in the finder (DGT/DVLA/KBA auto-detect your model and engine); 2) check the "Compatible vehicles" tab on this page, where we list every vehicle verified by our technical team; 3) if you cannot find your model, message us on WhatsApp with brand, model, engine and year — we reply during business hours (Mon–Fri 9:00–18:00 CET). The FK820 typically fits a wide range of European vehicles thanks to its standard DIN case format. ### Which batteries are equivalent to the Fulmen FK820? Directly interchangeable batteries (same dimensions, same polarity, same Ah and CCA) are the OEM equivalents from leading brands: Bosch, Tudor, Exide and, depending on the model, Banner or Yuasa. Exact equivalence depends on technology — an EFB cannot be replaced with a conventional battery in Start-Stop cars. See the "Equivalents" section to view recommended options at the same performance level. ### Which is better: Fulmen FK820 or an alternative from another brand? This battery and its equivalents from Bosch, Tudor or Exide are technically comparable: same dimensions, same voltage and same capacity. The differences are warranty (Varta and Bosch: 2 years; Tudor and Exide: 2 years on the equivalent line), manufacturing plant (Varta and Bosch share origin in the Clarios Group; Tudor and Exide belong to Exide Technologies) and price. For private use any of these brands will give 4-6 years of life. Compare them in the "Equivalents" section. ### What reviews does the FK820 model have? The product rating, when available, is shown on the product page next to the stars. You can also check our public Trustpilot profile at shop level (4.5/5 from 11,298+ verified reviews). Most-praised points: reliable cold start, lifespan above 5 years and fast delivery; most common complaints mention BMS-equipped cars that need OBD registration after fitting. ### What advantages does the Fulmen FK820 AGM battery offer over an EFB? AGM (Absorbent Glass Mat) technology uses absorbent fibreglass that retains the electrolyte, eliminating leaks and allowing up to 3× more charge/discharge cycles than a conventional battery. It is the recommended option when the car has advanced Start-Stop with regenerative braking (BMW EfficientDynamics, Mercedes Eco, Audi MHEV, Land Rover ECO, Volvo i-Stop). Withstands tilted positions, high vibration and extreme temperatures better than EFB. The Fulmen FK820 is fully original and meets European EN 50342-6 standards for advanced Start-Stop. ### Do I need to register the Fulmen FK820 on the car after installation? On most cars it is not strictly necessary — the alternator detects the new battery and adapts the charge automatically. It is recommended to register the battery via OBD so that the alternator applies the optimal charging profile from the first minute and extends the battery life as much as possible (especially on brands with sophisticated BMS: BMW, Mercedes, Audi, Volvo, Land Rover). Any workshop with an OBD scanner (~10-15 € labour) does it in 5 minutes. DIY apps: VCDS / Carista (VAG), Bimmercode (BMW), iCarsoft. If you do not register, the car will still start correctly — the alternator just takes a few days to adjust the profile. The Fulmen FK820 ships factory-charged at 80-90% so you can use it straight after fitting. ## Equivalent batteries - [EXIDE EK820](https://baterias.com/gb/battery-exide-ek820-12v-82ah-800a) - [TUDOR TK820](https://baterias.com/gb/battery-tudor-tk820-12v-82ah-800a) ## Technical team (editorial authorship) The FAQs, guides and comparisons on this site are reviewed by the baterias.com technical team — over 25 years of experience validating automotive batteries. → https://baterias.com/gb/technical-team --- *baterias.com — Automotive batteries · 2026-08-25*