lead acid battery charging, will this work

[old martParticipant @oldmart]

My next door neighbor has a van that doesn't get used much, and he has a solar cell array stuck to the roof that keeps the battery charged.

[Cornish JackParticipant @cornishjack]

Thank you, Robert and Peter – The grinder is a Lidl branded 20v item and dismantling it (VERY tricky) shows a compact installation with a thin oblong completely sealed unit between the battery and the on/off switch. This, I assume, contains the monitor and balance functions and is (for all practical purposes) internally inaccessable. The monitor item I was considering was somewhat simpler than your item, Peter, having built-in digital voltage read-outs and (I assumed) intended to be wired directly between the battery and on/off switch to give real-time battery voltage state. The thought was to monitor this value and stop using the grinder when the indication was at an appropriate (rechargeable) level. The supplied charger has all the necessary protection circuits and is fully serviceable, as is the battery pack (at the moment). There are probably difficulties which I haven't appreciated due to lack of knowledge – hence the call for advice.

rgds

Bill

[Perko7Participant @perko7]

At our club, even though we have mains power, all our loco batteries are recharged by a solar charger on the roof of the storage shed. Only a small solar panel, with controller, will keep the batteries topped up forever.

[Anonymous]

Posted by duncan webster on 04/11/2020 17:10:32:

In brief the solar anel issue is that it charges the battery so well that it is outputting over 14v. The chip didn't like it, it was OK on 12, but 14.4 was too much for the little things.

Although it varies with temperature the normal charge voltage for lead acid batteries is 2.45V per cell, or 14.7V for a nominal 12V battery.

Andrew

[Robert Atkinson 2Participant @robertatkinson2]

Posted by Cornish Jack on 04/11/2020 21:23:27:

Thank you, Robert and Peter – The grinder is a Lidl branded 20v item and dismantling it (VERY tricky) shows a compact installation with a thin oblong completely sealed unit between the battery and the on/off switch. This, I assume, contains the monitor and balance functions and is (for all practical purposes) internally inaccessable. The monitor item I was considering was somewhat simpler than your item, Peter, having built-in digital voltage read-outs and (I assumed) intended to be wired directly between the battery and on/off switch to give real-time battery voltage state. The thought was to monitor this value and stop using the grinder when the indication was at an appropriate (rechargeable) level. The supplied charger has all the necessary protection circuits and is fully serviceable, as is the battery pack (at the moment). There are probably difficulties which I haven't appreciated due to lack of knowledge – hence the call for advice.

rgds

Bill

Very hard to tell what that component is without information or disassembly. Likely not a typical lithium battery protection circuit though. These are normally inside the battery pack. It could be over-current protection, over discharge protection, over temperature protection a combination or something completely different.

Does it have any markings?

How mainy wires ? all the same size?

Robert G8RPI.

[Author]

Posts