Trickle charger advice/recommendations.

[DavidCM]

I've got a 2020 RC300h,which wouldn't start this morning.CalledLexus Roadside Assistance who turned up and jump started it.

As soon as I tried to start,I guessed that it was the 12v Battery.I think I now need to get a trickle charger,but which make and model...Ctek and Noco are mostly recommended here..so any suggestions as to which particular model I should go for?.There is power to the carport where the car is kept 

To add to this, it may be useful for the charger to also charge a 21ah lawnmower Battery.

Any advice or recommendations would be much appreciated.

[Brian R]

Very topical subject given just last week I ordered and had delivered the same day one of these:

10 amp battery charger/maintainer

Unlike most CTEK's this can charge at 10 amps and apparently maintain. I've already charged 2 deeply discharged field batteries used on electric fencing and no complaints (so far) from the equestrian quarter. CTEK and their like tend to have circa 5 amp outputs, and they will very often be unable to kick-start a fully discharged Battery, whereas I know from practice my old faithful conventional 12 amp charger can and does.

So far it appears to be doing its job and I would also add it replaced a very short (1 day) experience with a Ring charger/maintainer which in the event was a complete waste of time on all accounts.

[ColinBarber]

I’ve three Noco charger that were used permanently over lockdown which kept the batteries healthy. One 1 amp and the other two 5 amp models. If you are just looking to keep a Battery topped up then the small one is fine, but it would take a very long time to charge a flat Battery. 
 

I did purchase one similar to above from amazon but the voltage reading it was giving was 0.2v below the actual voltage I measured from the Battery. Fine to charge a Battery up but had the potential to overcharge if left connected so I returned it. Probably just a faulty unit but I didn’t take a chance and just got another Noco.

Noco has a mode to charge a completely flat Battery, unlike CTEK. 

[DavidCM]

Thank you both,Colin and Brian ,for your suggestions.