Car Mechanics (UK)
Can you recommend a battery charger with a jump-start function for use on my 2012 VW Polo 1.4 petrol or any vehicle fitted with an ECU. Having owned various jumpstarters and power packs, all of which had issues such as lack of power and heavy short leads, I was looking to get a mains battery charger.
The units I have been considering are the Ring RCB320 or RECB320. My worry is that the jump-start function might not be safe on the electronics. Do these models have spike and short protection? Also, do they have to be attached to the battery’s positive terminal and the body of the vehicle, and does the battery have to be charged a little before using the jump-start? Regarding the battery charger function, are they safe to attach to the battery without removing the battery connections to charge the battery? Halfords says the Ring RCB320 is not suitable for AGM batteries, but I have no idea if I have one fitted as the battery is still the original. Would this advice also apply to the jump-start function?
Modern battery chargers are designed to jump-start modern vehicles and should be safe to use. The two Ring chargers you mentioned can sense the battery and will protect it from overcharging, as well as preventing any power spikes that may cause damage. The attachment instructions in the manual state that the red lead should be attached to the positive terminal, while the black negative lead clips to the vehicle’s chassis.
AGM stands for absorbent glass mat and these batteries are usually found in motorcycles, because they do not leak, or high-end vehicles with a large electrical demand. They are now also being used on vehicles fitted with stop-start technology. It would not be suitable to use the charger’s jump-start function on a AGM battery. However, from the data I have, your VW Polo is not fitted with an AGM battery.
The 80-amp jump-start function is probably not high enough to start a vehicle with a completely depleted battery. If your battery was in this condition I would expect it to need to undergo a slow charge before the jump-start would work. A professional jump-start would deliver at least 280 amps on the start function.