Topic: Battery voltage drop

[danny7147]

One for the electrics guy's...

I've now had the control box and POD repaired, paid a laptop shop to build me a new harness. Electrically, it's perfect, but the range is still about half a mile before the the dreaded beep! So, a multimeter tells me that the two batteries I use are acting a little strangely. It may be normal, but I think it's the root cause.

Battery 1, a 40Ah, generates a perfectly acceptable 13.23V when it comes off of charge. A test 15 minutes later shows 13.03V, and after 30 minutes it shows 12.74V. IrVIng lasts about half a mile.

The other, a 35Ah, generates a huge 13.42V on full charge, dropping to 12.92V after 15 minutes, and 12.10V after 30 minutes which explains why it barely lasts a few yards!

Now, before short circuits are blamed, they were tested unplugged and unused. The voltage drop is occurring while the batteries are resting. Is this normal? Are they both duff?

[radiomarty]

Hi Danny - you need to do a load test (drop test) on the batteries to see there condition - most garages have this facility and the friendly ones do it for free if they think you may possibly buy a new battery from them