# Auxiliary battery Tudor TK151 12V 15Ah 200A AGM ![Auxiliary battery Tudor TK151 12V 15Ah 200A AGM](https://baterias.com/1125-home_default/battery-tudor-tk151-15ah-200a.jpg) > Tudor TK151 auxiliary battery 12V 15Ah 200A AGM. Start-Stop Auxiliary range. Dimensions 150×90×145 mm, + terminal on the left. Check fitment by plate. **Category:** [Auxiliary Batteries](https://baterias.com/gb/auxiliary-batteries) → [TUDOR](https://baterias.com/gb/tudor) - **Canonical URL**: https://baterias.com/gb/battery-tudor-tk151-15ah-200a - **Language**: en-GB - **Brand**: TUDOR - **Reference**: BCOM-TUDOR-TK151 - **EAN**: 3661024056571 - **MPN**: TK151 - **Price**: 64,95 € (VAT incl., Spain) - **Last updated**: 2026-10-28 - **Stock**: In stock ## Technical specifications | Feature | Value | |---|---| | Brand | TUDOR | | Reference | TK151 | | Model | TUDOR AUXILIAR | | Voltage (V) | 12 V | | Largo | 150 mm | | Ancho | 90 mm | | Alto | 145 mm | | Tecnología | AGM | | EAN | 3661024056571 | | Terminal layout | Positive terminal on the left | | Cold cranking amps (EN) | 200 A | | Capacity (C20) | 15 Ah (c20) | ## Quick description **Tudor TK151 12V 15Ah 200A** is an auxiliary battery: it supports the Start-Stop system and on-board electronics during stops, without draining the main battery. ## Why this auxiliary 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 15 Ah C20 🔋 Cold cranking 200 A EN-1 📏 Dimensions 150×90×145 mm ⚙️ Technology AGM 🧭 Polarity Positive on the left ⚖️ Weight 4,8 kg 🏷️ Model TUDOR Start-Stop Auxiliary ## Description ## Auxiliary battery Tudor TK151 Auxiliar 15Ah 200A 12V 12*V* Voltage 15*Ah* Capacity 200*A* Cold cranking 4.80*kg* Weight Designed for the auxiliary network of cars with advanced Start-Stop and heavy electronics, the **Tudor TK151** from the **Auxiliar** range stabilises the voltage with **15 Ah** with AGM technology. It measures 150 × 90 × 145 mm and the positive terminal on the left, the format sought by anyone replacing a 15 Ah battery in vehicles with an auxiliary battery. - Maintenance-free. - Sealed AGM: safe when installed in the cabin. - Stabilises the onboard network voltage. - AGM technology: absorbed electrolyte, no spills, can be mounted at an angle. ### Dimensions, polarity and mounting In terms of format, the Tudor TK151 measures 150 × 90 × 145 mm (length × width × height) and weighs 4.80 kg. The positive terminal on the left decides which side the cables end up on: it is the detail that causes most buying mistakes, so check it before ordering. For a direct replacement, the current battery tray must accept these dimensions and the same terminal layout; otherwise adapters will be needed or the hold-down will change. ### What the Tudor TK151 is for With 15 Ah, the Tudor TK151 is the direct replacement for the original auxiliary battery in the auxiliary network of cars with advanced Start-Stop and heavy electronics. Check that it matches your current battery in dimensions, terminals and hold-down: this reference has a weight of 4.80 kg. ### The Tudor TK151: Auxiliar range and AGM technology Within the Tudor catalogue, the **Auxiliar** series groups the references designed for this use. The TK151 is the 15 Ah model of that family, with the same performance as its siblings in other sizes. AGM means the acid is held in a glass mat instead of floating free. That is why the battery can be installed in the cabin without gases, survives more cycles and recovers its charge quickly. ### Tudor: the maker behind the TK151 Tudor has made batteries in Spain for more than a century and remains one of the brands most trusted by Spanish workshops for reliability and value. All the Tudor batteries in our catalogue are genuine product, recently manufactured and covered by the manufacturer's warranty. ### Official warranty The Tudor TK151 comes with the **manufacturer's official warranty** against manufacturing defects. If it fails through a defect within the warranty period, we replace it at no cost to you. ### Care and maintenance The auxiliary battery works alongside the main one: if a support-network fault warning appears, check both. Replace it with the same technology and capacity as the original. ### Delivery times and returns Order **before 6:00 pm** with stock available and it leaves today: mainland Spain and Portugal receive it in 24-48 working hours, the islands and the rest of the EU in 3 to 5 days. You have **14 days** to return it if it has not been installed, with free collection on the mainland, and shipment tracking by email. ## Frequently asked questions ### Is the Tudor TK151 an AGM battery and what are the benefits of AGM? Yes. The Tudor TK151 is AGM (Absorbent Glass Mat): sealed lead-acid, with the electrolyte absorbed in glass fibre. 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. ### Is the TK151 model suitable for Start-Stop cars? Yes: being AGM, the Tudor TK151 is designed for Start-Stop cars. 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. ### How long does the Tudor TK151 battery last? As a guide, you can expect the Tudor TK151 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. ### What are the dimensions of the Tudor TK151 battery? 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. ### On which side is the positive of the TK151 model? On the Tudor TK151, the polarity is positive on the left. To check, stand the battery in front of you with the terminals nearest you: the positive (+) is the one with the red ring. A change of polarity from the original means longer cables or a reconfigured system and can cause a short circuit: check it before ordering. ### Will the Tudor TK151 battery fit my car? 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)). Always cross-check with what the car manufacturer states in the owner's handbook. ### Which batteries are equivalent to the Tudor TK151? See the "Equivalents" section of this page for the recommended options at the same performance level. Mind the technology: in Start-Stop cars an EFB is not swapped for a conventional battery. To replace the Tudor TK151 without modifications, the other battery must be identical in size, polarity, Ah and CCA. ### Tudor TK151 or Exide EK151: which one to choose? Same case and same fitting as the TK151, from Exide. Compared with the TK151 it has the same Ah and cranking power. It costs 10,35 € less. If you want to save or the TK151 is out of stock, it is the safe alternative: same dimensions, same polarity and official warranty. ### What advantages does the Tudor TK151 AGM battery offer over an EFB? This TK151 delivers 200 A cold cranking (EN). 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. 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). ### Do I need to register the Tudor TK151 on the car after installation? 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). 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. If you do not register the TK151, it will keep starting fine while the alternator adjusts the profile over a few days. ## Equivalent batteries - [EXIDE EK151](https://baterias.com/gb/battery-exide-ek151-12v-15ah-200a) ## Technical team (editorial authorship) The FAQs, guides and comparisons on this site are reviewed by the baterias.com technical team — automotive battery specialists since 2012. → https://baterias.com/gb/technical-team --- *baterias.com — Automotive batteries · 2026-11-11*