This week I had to change the battery of my 1970 280sl. In a nearby battery shop I asked for advice.
According to the manual the car needs a 55 Amp battery. A W113 expert told me to buy a 70 Amp one as it has a two times better starting output. After telling this to the battery specialist he drew my attention to an US-type battery of 50 Amp.
It had the same dimension as the battery to be changed so it would fit. It was totally waterproof sealed and could even be used upside down. It has a inovative builtup inside: no plates but 6 colums of winded up plates. The columns are reflected in a waved outside shape of the exterior of the battery. The concept, developed by the US army and recently issued for the civil market, results in for me unbelievable qualities:
- a starting output of three times the output of a 'normal' 55 Amp
- 50 Amp would equal to 80 Amp of a conventional battery
- a 50 Amp battery will be charched in short time and therefor is very comfortable in case of short rides.
- decharging is possible till 80% without damage (sulfatation) in stead of 50%/40% with normal batteries.
- a life cycle of 5-6 years in stead of 3-4 years
- really total maintenance free
At the moment I decided to buy this US-made wonder I noticed that in the US the + and - poles are (always) the other way roud compared to Euro batteries. The wires of my sl were not long enough to reach the poles when the battery was placed with the poles directed to the front of the car so that the poles would match the car + and - wire. The shop did not have parts which could bridge the lacking distance from the front of the battery withe poles to the back. The only working but also costy solution would be to adjust the wires. As I needed a properly working battery immediately I finally bought a conventional one of 70 Amp.
Now my questions:
- does anyone have knowledge of or has anyone experience with these 50 Amp US batteries?
- does anyone know if there are parts with which the poles can be brought to the other side of the battery so that adjusting of the wires can be avoided?
Gerard Wuisman
1970 280sl
