Battery charging.

[martin j.]

Washed the Seat and decided my Honda was boggin despite having been the garage for weeks, but no the battery was flat, so I coupled the battery charger and went to do something else, back after 4 hours still nothing doing, realised that with the charger attached even the interior light wasn’t coming on. Rummaged in the garage and found an old school 40+year old non intelligent charger, coupled this and success, seems modern chargers won’t recognise a completely flat battery and so doesn’t know it should be charging, after a couple of hours the Honda battery had enough charge for me couple in the newer one and left it coupled overnight, all ok this morning. Hope this might save someone the same problem again.

 

[RUM4MO]

Yes, possibly two issues, the battery voltage was initially too low and most smart chargers people are buying only hand over 5 amps max - and some of them will hand over nothing if over stretched ie crowbarring.

These older not so smart basic chargers do still have a use, I've given away my oldest two but kept an "RAC" 8AMP one I bought in Halfords 10 years ago, it seems to be safe enough not to cause any damage if used while the battery is still connected - well I ended up doing that a few times with my older daughter's previous car which was a late 2009 Ibiza 1.4 16V SC.

 

[Walone]

Washed the Seat and decided my Honda was boggin despite having been the garage for weeks, but no the battery was flat, so I coupled the battery charger and went to do something else, back after 4 hours still nothing doing, realised that with the charger attached even the interior light wasn’t coming on. Rummaged in the garage and found an old school 40+year old non intelligent charger, coupled this and success, seems modern chargers won’t recognise a completely flat battery and so doesn’t know it should be charging, after a couple of hours the Honda battery had enough charge for me couple in the newer one and left it coupled overnight, all ok this morning. Hope this might save someone the same problem again.

What 'intelligent' charger were you using?

 

[RADIOTWO]

If any one is having the same problem as Martin, all you have to do is connect the flat battery to another (good) battery leave it for about 1Hr
then put your smart charger on and it should start to charge

 

[martin j.]

What 'intelligent' charger were you using?

It a Bosch only 4amp output, no idea of any model number.

 

[cupra14]

There's a sort of rule of thumb that a really flat battery (if it'll recover and they won't if left flat for long) needs in amps around 1/10 of its Ah rating. So a 60Ah needs 6A or so for quite a while.

An old-fashioned dumb charger sounds ideal

 

[Walone]

It a Bosch only 4amp output, no idea of any model number.

I have a CTEK MXS 5.0 (widely recognised as one of the best smart chargers) and it has a 'Reconditioning' program which states "Use to return energy to empty batteries, Recon your battery once per year or after DEEP discharge to maximise lifetime and capacity".
Whether it would have worked on your battery is another matter.