after several short hops my v70 is low on batt volts,if i connect a set of cables from the batt to a plug in the boot (to charge batt without removing batt cage) if using a low charge once a week will any harm be caused to the batt or the computer.
Thanks in advance Raymondo

 

I would use what is termed a "battery maintainer". I did not look to see what area you are located in but if it is the U.S., Sears sells one for appx. $40.00. You can leave it connected all year and it will not boil the battery such as what will happen if you use a "regular" battery "charger" for an extended period of time. I use one in the winter on my summer autos and the battery is fresh in the Spring. Make sure that your battery has water in it as Volvo's are famous for boiling out the water. If your level is low that will not allow the battery to be charged fully. In fact, prior to connecting any battery charging device, make sure the battery is full of distilled water or the result could be rather explosive!
Reg