Apparently the battery in my M3W (a Yuasa - same size as original Banner) has died again while it is in storage in France. I suspect that the CTEK conditioner that I left in the car, did not get connected as instructed. I will now consider going lithium. I have a solid state H-D rectifier/charge controller, which apparently works well with Lithium batteries. As I cannot currently access the car, can someone please advise me the dimensions of the original battery. Selection of Lithium batteries is quite limited in France, with most being send mail order from Germany, so as and when permitted, I may need to take one out with me. One reason for going lithium is that charging a lead acid battery in ambient temperatures of 45ºC and probably 55-60º or more under the bonnet, apparently shortens their life considerably.
Wilson