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Solar powered trickle charger

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Several questions, sorry.

1. is there a way to trickle charge multiple batteries from one trickle charging unit (where a 240v mains supply is available)?

2. is there a way to trickle charge multiple batteries from one trickle charging unit (where there is only access to a solar panel and no mains feed)?

3. in the situations above (1 and 2) does it matter that there is a combination of battery types (wet lead-acid and deep cycle gel batteries)?

4. can anyone recommend a weatherproof solar panel to drive this potential setup?

5. can anyone recommend a trickle charger to run off a solar panel to charge multiple 12v batteries?


Batteries currently:

2 x wet lead-acid batteries (50-60 amp hour each); but these could go in time.

2 x gel deep cycle batteries (80 amp hour); very old and again could go in time.

2 x gel deep cycle batteries (110 amp hour); eventually will end up with just these at the observatory.



We have an observatory with no mains power. The mount runs at 24v, lighting at 12v. We are looking for solutions to trickle charge the batteries on site, and avoid the need of someone having to lug the 110 amp hour batteries away each time the observatory is used. The smaller batteries are being used as these are easier to carry, but the goal would be to end up with just the two large deep cycle batteries for the mount, and maybe one or two of the other batteries for lighting or to provide a 12v feed to someone who may bring a scope and save them bring power too. We don't want to explore wind power for the time being.


Thanks for any replies.

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I used these for my Bee Hive monitoring setup.  It is the 40W panel with a 12Ah 12V SLA.  My system takes approx 150mA and this struggles in the winter to keep the battery topped up for an overnight run in the winter.  Use one of the online calculators to determine the size of panel


To charge multiple get an MPPT charger as this will allow you to connect multiple batteries and this type of charger will maximize the energy available from the panel


You can't mix the types on one charger.  You need to set up whether it's Gel, SLA or Flood as they all have differing charging characteristics but you can connect multiple chargers to one panel

Edited by MarkyD

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