Choosing the right battery for a Mercedes-Benz CLK W209 (2002–2009) is essential to maintain optimal performance and avoid electrical issues, especially given the variety of petrol and diesel engines available in this model range. Since none of the engine variants in the W209 feature Start-Stop technology, traditional lead-acid batteries are fully sufficient. The battery specifications, however, vary significantly depending on the engine type and its power requirements.
For drivers of models like the 200 CGI, 200 Kompressor, or 240, which are equipped with smaller petrol engines, a battery with a capacity between 60 and 65 Ah and a cold cranking amperage (CCA) ranging from 540 to 640 A is recommended. Suitable battery types are standard 12V lead-acid, which are widely available and cost-effective. Some of the compatible models for these engines include the Bosch S40 05, Bosch S50 05, Exide EA640, and Varta D15. These examples represent high-quality batteries known for reliability and performance, making them solid choices for daily driving needs.
If your CLK has a larger petrol engine like the 280, 320, or 350, the electrical demand increases, especially during cold starts or when using multiple accessories at once. For these versions, batteries in the 74–78 Ah range with 680–780 A CCA are advised. Examples of matching batteries include the Exide EA770, Bosch S50 08, and Varta E44. These batteries provide more reserve capacity, which ensures consistent energy delivery during short trips or in colder climates. It’s always a good idea to check the battery dimensions and terminal layout to confirm compatibility.
For owners of high-performance models like the CLK 500, 55 AMG, and CLK DTM AMG, the need for a powerful battery is even more pronounced due to larger engine displacements and the presence of additional electronic systems. These engines perform best with batteries offering between 80 and 90 Ah and 640–800 A CCA. Sample compatible models include the Exide EA900, Bosch S50 11, and Varta F19. A well-performing battery in this range ensures rapid engine cranking and stable voltage for premium features like high-end audio systems, memory seats, and advanced climate control.
The pinnacle of power in the CLK lineup, the 63 AMG, demands even more robust battery performance. For this flagship model, batteries with 95–100 Ah and 800–900 A CCA are recommended to meet the power-hungry needs of the massive V8 engine and its electrical systems. Some compatible battery examples are the Bosch S50 13, Exide EA1000, and Varta H3. These batteries are not only larger in capacity but also built with higher durability, making them ideal for sport-oriented or demanding driving conditions.
For diesel variants such as the 220 CDI, 270 CDI, and 320 CDI, high cold cranking power is critical for reliable starts, especially in cold weather where diesel engines can be more difficult to ignite. These models require 80–90 Ah batteries with CCA values between 640 and 800 A. Examples of suitable models are the Lucas LP115, Exide EB800, and Varta F16. Diesel engines benefit significantly from batteries with high burst energy due to their higher compression ratios.
A helpful tip when replacing your battery in the CLK W209 is to always reset the onboard electronics if necessary, as some systems may require reinitialization after a power loss. Additionally, while AGM batteries are often used in newer vehicles with Start-Stop technology, they are not necessary for the CLK W209 unless additional electrical loads or future modifications justify the upgrade.
Interestingly, Mercedes-Benz positioned the battery in the engine bay for most CLK W209 models, making access and replacement relatively straightforward compared to modern vehicles where batteries are often hidden in the trunk or under the seats. This traditional layout makes DIY battery swaps more accessible for confident car owners.
To ensure the longevity of your new battery, consider driving your vehicle regularly and avoiding short trips that don’t allow the alternator enough time to recharge the battery fully. With the right battery properly installed, the Mercedes-Benz CLK W209 can continue to offer its signature blend of comfort and performance for years to come.
Mercedes-Benz CLK in version W209 was produced in the years 2002 – 2009. Below we present the specifications of batteries suitable for specific engines.
Basic parameters of batteries suitable for Mercedes-Benz CLK (2002-2009):
| Layout | Terminal types | Base hold-down |
|---|---|---|
| 0 – positive on the right side | 1 | B13 |
Mercedes-Benz CLK W209 – petrol engines:
- 200 CGI
- 200 Kompressor
- 240
| Model | Capacity and CCA | Dimensions (LxWxH) | Price |
|---|---|---|---|
| Bosch S4 S40 05 | 60 Ah 540 A | 242x175x190 mm | More |
| Bosch S5 S50 05 | 63 Ah 610 A | 242x175x190 mm | More |
| Exide Excell EB620 | 62 Ah 540 A | 242x175x190 mm | More |
| Exide Premium EA640 | 64 Ah 640 A | 242x175x190 mm | More |
| Halfords Standard HCB 027 | 62 Ah 550 A | 242x175x190 mm | More |
| Lucas Premium LP027 | 60 Ah 540 A | 243x175x190 mm | More |
| Lucas Supreme LS027 | 65 Ah 640 A | 242x175x190 mm | More |
| Varta Blue Dynamic D24 | 60 Ah 540 A | 242x175x190 mm | More |
| Varta Silver Dynamic D15 | 63 Ah 610 A | 242x175x190 mm | More |
Mercedes-Benz CLK W209 – petrol engines:
- 280
- 320
- 350
| Model | Capacity and CCA | Dimensions (LxWxH) | Price |
|---|---|---|---|
| Bosch S4 S40 08 | 74 Ah 680 A | 278x175x190 mm | More |
| Bosch S5 S50 08 | 77 Ah 780 A | 278x175x190 mm | More |
| Exide Excell EB740 | 74 Ah 680 A | 278x175x190 mm | More |
| Exide Premium EA770 | 77 Ah 760 A | 278x175x190 mm | More |
| Halfords Standard HCB 096 | 76 Ah 680 A | 278x175x190 mm | More |
| Lucas Premium LP096 | 75 Ah 680 A | 278x175x190 mm | More |
| Lucas Supreme LS096 | 78 Ah 780 A | 278x175x190 mm | More |
| Varta Blue Dynamic E11 | 74 Ah 680 A | 278x175x190 mm | More |
| Varta Silver Dynamic E44 | 77 Ah 780 A | 278x175x190 mm | More |
Mercedes-Benz CLK W209 – petrol engines:
- 500
- 55 AMG
- CLK DTM AMG
| Model | Capacity and CCA | Dimensions (LxWxH) | Price |
|---|---|---|---|
| Bosch S4 S40 11 | 80 Ah 740 A | 315x175x190 mm | More |
| Bosch S5 S50 11 | 85 Ah 800 A | 315x175x190 mm | More |
| Exide Excell EB800 | 80 Ah 640 A | 315x175x190 mm | More |
| Exide Premium EA900 | 90 Ah 720 A | 315x175x190 mm | More |
| Lucas Premium LP115 | 80 Ah 670 A | 317x175x190 mm | More |
| Varta Blue Dynamic F16 | 80 Ah 740 A | 315x175x190 mm | More |
| Varta Silver Dynamic F19 | 85 Ah 800 A | 315x175x190 mm | More |
Mercedes-Benz CLK W209 – petrol engines:
- 63 AMG
| Model | Capacity and CCA | Dimensions (LxWxH) | Price |
|---|---|---|---|
| Bosch S4 S40 13 | 95 Ah 800 A | 353x175x190 mm | More |
| Bosch S5 S50 13 | 100 Ah 830 A | 353x175x190 mm | More |
| Exide Excell EB950 | 95 Ah 800 A | 353x175x190 mm | More |
| Exide Premium EA1000 | 100 Ah 900 A | 353x175x190 mm | More |
| Halfords Standard HCB 019 | 95 Ah 850 A | 353x175x190 mm | More |
| Lucas Premium LP019 | 95 Ah 800 A | 354x175x190 mm | More |
| Lucas Supreme LS019 | 100 Ah 850 A | 354x175x190 mm | More |
| Varta Blue Dynamic G3 | 95 Ah 800 A | 353x175x190 mm | More |
| Varta Silver Dynamic H3 | 100 Ah 830 A | 353x175x190 mm | More |
Mercedes-Benz CLK W209 – diesel engines:
- 220 CDI
- 270 CDI
- 320 CDI
| Model | Capacity and CCA | Dimensions (LxWxH) | Price |
|---|---|---|---|
| Bosch S4 S40 11 | 80 Ah 740 A | 315x175x190 mm | More |
| Bosch S5 S50 11 | 85 Ah 800 A | 315x175x190 mm | More |
| Exide Excell EB800 | 80 Ah 640 A | 315x175x190 mm | More |
| Exide Premium EA900 | 90 Ah 720 A | 315x175x190 mm | More |
| Lucas Premium LP115 | 80 Ah 670 A | 317x175x190 mm | More |
| Varta Blue Dynamic F16 | 80 Ah 740 A | 315x175x190 mm | More |
| Varta Silver Dynamic F19 | 85 Ah 800 A | 315x175x190 mm | More |
If you’re still unsure which battery fits your Mercedes-Benz CLK , or if you want to help others in their selection, please send us a photo of your current battery in the comment section at the bottom of the page. You can also send the picture to contact@whatbattery.co.uk (we will place it in the comments to also help other users). Be sure to specify the car model, year, type, as well as the engine capacity and power. We’ll do our best to assist you!