# Mercedes-Benz SLK battery: what each engine takes, with prices

> The Mercedes-Benz SLK has run through 3 generations between 1996 and 2025, and we cover every one of them with 7 compatible batteries: 13 to 80 Ah, 200 to 800 A of cold cranking, from 64.95 € with VAT.

## Which battery does a Mercedes-Benz SLK take?

It depends on the engine. Mercedes-Benz SLK owners mostly buy Varta E44 Dynamic SLI 77Ah (85.40 €), Varta D15 Dynamic SLI 63Ah (81.80 €) and Tudor TB740 Technica 74Ah (61.95 €) from us. The table shows the recommended battery for each engine with its price (VAT included) and a link to its page; with your number plate or VIN we tell you the exact one in seconds.

## Recommended battery for each Mercedes-Benz SLK engine

| Engine | Generation | Recommended battery | Price | URL |
|---|---|---|---|---|
| 200 Kompressor (171.442) (120 kW / 163 CV) | Slk II (2004–2011) | Varta E11 Dynamic SLI 74Ah | 74,95 | https://baterias.com/gb/car-batteries/mercedes-benz/slk-r171/200-kompressor-171442-120-kw-163cv |
| 350 (171.456) (200 kW / 272 CV) | Slk II (2004–2011) | Varta E44 Dynamic SLI 77Ah | 85,40 | https://baterias.com/gb/car-batteries/mercedes-benz/slk-r171/350-171456-200-kw-272cv |
| 350 (171.458) (224 kW / 305 CV) | Slk II (2004–2011) | Varta E44 Dynamic SLI 77Ah | 85,40 | https://baterias.com/gb/car-batteries/mercedes-benz/slk-r171/350-171458-224-kw-305cv |
| 200 (170.435) (100 kW / 136 CV) | Slk I (1996–2004) | Varta D24 Dynamic SLI 60Ah | 64,95 | https://baterias.com/gb/car-batteries/mercedes-benz/slk-r170/200-170435-100-kw-136cv |
| 230 Kompressor (170.447) (142 kW / 193 CV) | Slk I (1996–2004) | Varta E44 Dynamic SLI 77Ah | 85,40 | https://baterias.com/gb/car-batteries/mercedes-benz/slk-r170/230-kompressor-170447-142-kw-193cv |
| 230 Kompressor (170.449) (145 kW / 197 CV) | Slk I (1996–2004) | Varta E44 Dynamic SLI 77Ah | 85,40 | https://baterias.com/gb/car-batteries/mercedes-benz/slk-r170/230-kompressor-170449-145-kw-197cv |
| 320 (170.465) (160 kW / 218 CV) | Slk I (1996–2004) | Varta E44 Dynamic SLI 77Ah | 85,40 | https://baterias.com/gb/car-batteries/mercedes-benz/slk-r170/320-170465-160-kw-218cv |
| 200 (172.448) (135 kW / 184 CV) | Slk III (2011–2025) | Varta A7 Dynamic AGM 70Ah | 134,95 | https://baterias.com/gb/car-batteries/mercedes-benz/slk-r172/200-172448-135-kw-184cv |
| 200 Kompressor (171.445) (135 kW / 184 CV) | Slk II (2004–2011) | Varta E44 Dynamic SLI 77Ah | 85,40 | https://baterias.com/gb/car-batteries/mercedes-benz/slk-r171/200-kompressor-171445-135-kw-184cv |
| 200 Kompressor (170.444) (120 kW / 163 CV) | Slk I (1996–2004) | Varta E44 Dynamic SLI 77Ah | 85,40 | https://baterias.com/gb/car-batteries/mercedes-benz/slk-r170/200-kompressor-170444-120-kw-163cv |
| 200 (172.434) (135 kW / 184 CV) | Slk III (2011–2025) | Varta A6 Dynamic AGM 80Ah | 149,95 | https://baterias.com/gb/car-batteries/mercedes-benz/slk-r172/200-172434-135-kw-184cv |
| 250 (172.447) (150 kW / 204 CV) | Slk III (2011–2025) | Varta A7 Dynamic AGM 70Ah | 134,95 | https://baterias.com/gb/car-batteries/mercedes-benz/slk-r172/250-172447-150-kw-204cv |
| 250 CDI / d (172.403) (150 kW / 204 CV) | Slk III (2011–2025) | Varta A6 Dynamic AGM 80Ah | 149,95 | https://baterias.com/gb/car-batteries/mercedes-benz/slk-r172/250-cdi-d-172403-150-kw-204cv |
| 300 (172.438) (180 kW / 245 CV) | Slk III (2011–2025) | Varta A6 Dynamic AGM 80Ah | 149,95 | https://baterias.com/gb/car-batteries/mercedes-benz/slk-r172/300-172438-180-kw-245cv |
| 350 (172.457) (225 kW / 306 CV) | Slk III (2011–2025) | Varta A7 Dynamic AGM 70Ah | 134,95 | https://baterias.com/gb/car-batteries/mercedes-benz/slk-r172/350-172457-225-kw-306cv |
| 55 AMG (172.475) (310 kW / 422 CV) | Slk III (2011–2025) | Varta A7 Dynamic AGM 70Ah | 134,95 | https://baterias.com/gb/car-batteries/mercedes-benz/slk-r172/55-amg-172475-310-kw-422cv |
| 280 (171.454) (170 kW / 231 CV) | Slk II (2004–2011) | Varta E44 Dynamic SLI 77Ah | 85,40 | https://baterias.com/gb/car-batteries/mercedes-benz/slk-r171/280-171454-170-kw-231cv |
| 300 (171.454) (170 kW / 231 CV) | Slk II (2004–2011) | Varta E44 Dynamic SLI 77Ah | 85,40 | https://baterias.com/gb/car-batteries/mercedes-benz/slk-r171/300-171454-170-kw-231cv |
| 55 AMG (171.473) (265 kW / 360 CV) | Slk II (2004–2011) | Varta E44 Dynamic SLI 77Ah | 85,40 | https://baterias.com/gb/car-batteries/mercedes-benz/slk-r171/55-amg-171473-265-kw-360cv |
| 55 AMG (171.473) (294 kW / 400 CV) | Slk II (2004–2011) | Varta E44 Dynamic SLI 77Ah | 85,40 | https://baterias.com/gb/car-batteries/mercedes-benz/slk-r171/55-amg-171473-294-kw-400cv |
| 200 Kompressor (170.445) (141 kW / 192 CV) | Slk I (1996–2004) | Varta E44 Dynamic SLI 77Ah | 85,40 | https://baterias.com/gb/car-batteries/mercedes-benz/slk-r170/200-kompressor-170445-141-kw-192cv |
| 32 AMG Kompressor (170.466) (260 kW / 354 CV) | Slk I (1996–2004) | Varta E44 Dynamic SLI 77Ah | 85,40 | https://baterias.com/gb/car-batteries/mercedes-benz/slk-r170/32-amg-kompressor-170466-260-kw-354cv |

## Mercedes-Benz SLK generations

Batteries change from one generation to the next. When two share a year, the body style — or simply the plate — settles it.

| Generation | Years | Body | Batteries | URL |
|---|---|---|---|---|
| Slk III | 2011–2025 | berlina | 18 | /gb/car-batteries/mercedes-benz/slk-r172 |
| Slk II | 2004–2011 | berlina | 17 | /gb/car-batteries/mercedes-benz/slk-r171 |
| Slk I | 1996–2004 | berlina | 14 | /gb/car-batteries/mercedes-benz/slk-r170 |

## Best-selling batteries for the Mercedes-Benz SLK

| Modelo | V | Ah | CCA (EN) | Tech | € VAT incl. | Stock | URL |
|---|---|---|---|---|---|---|---|
| Car battery Varta E11 Dynamic SLI 12V 74Ah 680A | 12 | 74 | 680 | PLOMO/ACIDO | 74,95 | ✓ | https://baterias.com/gb/battery-varta-e11-12v-74ah-680a |
| Car battery Varta E44 Dynamic SLI 12V 77Ah 780A | 12 | 77 | 780 | PLOMO/ACIDO | 85,40 | ✓ | https://baterias.com/gb/battery-varta-e44-12v-77ah-780a |
| Start-Stop battery Varta A7 Dynamic AGM 12V 70Ah 760A AGM | 12 | 70 | 760 | AGM | 134,95 | ✓ | https://baterias.com/gb/battery-varta-a7-agm-12v-70ah-760a |
| Car battery Varta D24 Dynamic SLI 12V 60Ah 540A | 12 | 60 | 540 | PLOMO/ACIDO | 64,95 | ✓ | https://baterias.com/gb/battery-varta-d24-12v-60ah-540a |
| Start-Stop battery Varta A6 Dynamic AGM 12V 80Ah 800A AGM | 12 | 80 | 800 | AGM | 149,95 | ✓ | https://baterias.com/gb/battery-varta-a6-agm-12v-80ah-800a |
| Car battery Varta D15 Dynamic SLI 12V 63Ah 610A | 12 | 63 | 610 | PLOMO/ACIDO | 81,80 | ✓ | https://baterias.com/gb/battery-varta-d15-12v-63ah-610a |
| Car battery Varta AUX14 Dynamic AUX 12V 13Ah 200A | 12 | 13 | 200 | AGM | 70,20 | ✓ | https://baterias.com/gb/battery-varta-aux14-12v-13ah-200a |

## How to know which battery your Mercedes-Benz SLK takes

The real shortcut is your registration number. It settles generation, engine and factory battery in seconds — exactly where most people get it wrong when buying.

Prefer to do it manually? Check the date of first registration on your V5C and match it against the generation table above. When a year straddles two generations, the body style decides it: five-door hatch, estate or coupé.

As a final check, look at the battery currently fitted: the label shows capacity (Ah) and cold cranking amps (A). Always replace with equal or higher figures, never lower, and keep the same dimensions and terminal layout.

## Start-Stop: which battery your SLK needs

The later SLK generations run Start-Stop, which puts the battery through hundreds of micro-cycles a day. These cars require EFB (basic Start-Stop) or AGM (Start-Stop with regenerative braking): fitting a conventional battery instead cuts service life to a few months and the ECU may disable the function. Rule of thumb: never downgrade from the technology fitted at the factory.

## Frequently asked questions

### Which battery does a Mercedes-Benz SLK take?
It depends on the engine. Mercedes-Benz SLK owners mostly buy Varta E44 Dynamic SLI 77Ah (85.40 €), Varta D15 Dynamic SLI 63Ah (81.80 €) and Tudor TB740 Technica 74Ah (61.95 €) from us. The table shows the recommended battery for each engine with its price (VAT included) and a link to its page; with your number plate or VIN we tell you the exact one in seconds.

### How much does a Mercedes-Benz SLK battery cost?
Between 64.95 € and 149.95 €, VAT included, depending on capacity and technology (lead-acid, AGM). Start-Stop versions (AGM or EFB) sit at the top of the range because they withstand many more cycles.

### How do I know which generation my SLK is?
By the registration year: Slk III (2011-2025); Slk II (2004-2011); Slk I (1996-2004). If your year falls in the overlap between two generations, tell them apart by body type (hatchback, estate or coupé) or use the plate finder, which settles it with no doubt.

### How long does a Mercedes-Benz SLK battery last?
Four to six years in normal use. Start-Stop batteries (AGM/EFB) tend to last a little less in city driving because of the number of restarts, but they are built for that cycling. If the car sits for weeks or cranks slowly in the cold, have it tested.

### How do I know the battery in my Mercedes-Benz SLK is worn out?
Typical signs: sluggish cranking in the cold, headlights dimming on start-up, a battery warning on the dash or electronics resetting. A workshop can check resting voltage (below 12.4 V means discharged) and cranking capacity in a minute.

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Updated: 2026-11-02 · https://baterias.com/gb/car-batteries/mercedes-benz/slk