Lead battery charging rates

[saltyrob]

Hi Folks,

I have fitted an Exide ET 650 flooded lead leisure battery which receives a charge via a 100 w solar panel and Victron SmartsSolar MPPT 75/10 solar charger. The charger allows the absorption and float rates to be adjusted to suit the battery. The charger factory default for the float charge was 13.8 v which I read somewhere was a little on the high side so have adjusted it to 13.4 v, to reduce the risk of overcharging. I cannot find any manufacturers info re suitable charging rates . I would be grateful for any can advice on this matter.

Also just out of interest , if a battery is disconnected and , 'rested', for a day or two f will it have a slightly larger voltage then when connected up even if no current is being drawn.

Many thanks

Rob

 

[MAURICE]

I have mine on float charge of 13.4v when not on the boat for extended periods and crank the voltage up to 14.8v when out for a few weeks. I have 180w solar with a charge controller cant remember the make. I did read on some web site about doing this. I've had my 3x 180 amp
lead acid batteries now for 4 years and still going strong. I do check on the water levels every time a visit the boat.

 

[geem]

Hi Folks,

I have fitted an Exide ET 650 flooded lead leisure battery which receives a charge via a 100 w solar panel and Victron SmartsSolar MPPT 75/10 solar charger. The charger allows the absorption and float rates to be adjusted to suit the battery. The charger factory default for the float charge was 13.8 v which I read somewhere was a little on the high side so have adjusted it to 13.4 v, to reduce the risk of overcharging. I cannot find any manufacturers info re suitable charging rates . I would be grateful for any can advice on this matter.

Also just out of interest , if a battery is disconnected and , 'rested', for a day or two f will it have a slightly larger voltage then when connected up even if no current is being drawn.

Many thanks

Rob

Do you have the Smart sense temperature module? With that fitted to provide reliable battery temperature information to the mppt, I would use 13.8v float.
You only need to rest batteries over night to get the true charge condition.

 

[PaulRainbow]

Hi Folks,

I have fitted an Exide ET 650 flooded lead leisure battery which receives a charge via a 100 w solar panel and Victron SmartsSolar MPPT 75/10 solar charger. The charger allows the absorption and float rates to be adjusted to suit the battery. The charger factory default for the float charge was 13.8 v which I read somewhere was a little on the high side so have adjusted it to 13.4 v, to reduce the risk of overcharging. I cannot find any manufacturers info re suitable charging rates . I would be grateful for any can advice on this matter.

Also just out of interest , if a battery is disconnected and , 'rested', for a day or two f will it have a slightly larger voltage then when connected up even if no current is being drawn.

Many thanks

Rob

I'd also set the float for those batteries to 13.4v.

Voltage reading for disconnected batteries should be the same as connected batteries with no load.