Thread: batterys

okay someone clever please my Rav4 every winter battery goes down lack of use having two vehicles does not help as only go about a few days a week okay so battery well done wont start but some power left have splashed out on fancy new charger has a rejuvenation mode got that on and blinking how long do I leave it on that mode before switching to charge instructions not clear at all many thanks

Once batteries start to die they can be hard to bring back. Project farm on youtube did a test involving connecting a welder to batteries to revive them, not my cup of tea boiling battery acid with a welder....
Probably best to replace it and invest in solar trickle charger.

Frosty weather lets you know the battery isn't what it used to be, hook the charger up for an odd day each week. Another tip I was given by auto-electrician is if the vehicle is sitting for length of time, disconnect the battery.

honestly "smart chargers" are crap.
the current draw on modern vehicles is pretty low, i can park my legacy 3.0 for a month and still start it.
get a new battery, if its going to be off the road for months then disconnect the battery and charge it every month or so. dont float charge them. not to good on liquid acid lead batteries.

one of the solar trickle chargers may be your new best friend....from all Ive heard they just poke a little bit in to keep battery topped up.
hopefully someone who has one will chime in with the skinny on them.

Yep solar battery chargers are the way to go.
I have probably gone through at least 5 or 6 batteries over the last 20 years due to them getting too flat from lack of use on my second vehicle.
Since i purchased a small solar panel and having it connected to my battery 24/7 i have managed to maintain 12.2v to 12.6v for the last 3 years with my vehicle sometimes not being used for up to 4 weeks at a time.
Cheap insurance at $300 to $400 per battery.
I don't have access to power for a trickle charger where the vehicle is parked, so solar is the next best option.
I think my solar panel is 15W

thanks for the comments guys the problem for me where I live would be theft of the solar unit sadly since I am presuming it has to sit on roof

Buy a slightly bigger solar panel, park your vehicle with the windscreen facing about north, and leave it inside your vehicle. You can get some panels with eyelets in the corners to add some suction cups to make it easier... use a budget solar charge controller to make sure you don't overcharge your battery (though unlikely).

Something like this would work ok: https://www.burnsco.co.nz/solar-pane...YaAtZpEALw_wcB
and this:
https://www.burnsco.co.nz/solarland-...YaAtZpEALw_wcB

though the cheap charge controllers on TM are ok as well:
https://www.trademe.co.nz/a/motors/c...ing/4791828389

or kit: https://www.trademe.co.nz/a/motors/c...ing/4793599786

I've used one to keep vehicle charged at home, and one for the local scout group when they go on jamboree with a portable solar panel and battery (leaders need to charge their phones!)

Ive got a couple Rav-4. A2013 diesel ( NZ)and a 2015 gas , the std battery is very small, had problems with the Rav-4 gas, in the cold, here in Canada, the Factory battery is only 550 amp, lots of room for a bigger battery, ive got 1000 amps in both now, and havnt had a problem since,
You can try a smart charger, it wont likey work, once battery has deteriorating plates it pretty much over, I probably change 200 batteries a yera on earth moving equipment, but we have extremely cold conditions,
A solar charger hard wired in on the roof will be out of sight for the most part,
I have a cigarette lighter charger, plugs in to cigarette lighter and puts a small charge in, works for cars that sit, this may be another option.

https://www.repco.co.nz/globes-batte...5-0/p/A1247337

We keep our Honda 4wheeler hooked up to this. Brilliant. A mate in has a house in Sydney who is well heeled has his RAV hooked up to a car size as he only gets over 1/4erly.

Originally Posted by Barry the hunter

thanks for the comments guys the problem for me where I live would be theft of the solar unit sadly since I am presuming it has to sit on roof

This is the updated version of what i have.
It can suction to inside you front windshield so it theft proof unless they break in to the vehicle.
Mine hangs off a bungy outside the vehicle on a post off my carport facing North and clamped to my vehicle battery under the hood so only a cable and the panel are able to be grabbed.
With this updated version you have 2 options , 1) inside the vehicle or 2) outside like mine.
Something like this may be an option for you and reasonably priced.

https://www.thebatterycellonline.co....tt_solar_panel

Originally Posted by Barry the hunter

okay someone clever please my Rav4 every winter battery goes down lack of use having two vehicles does not help as only go about a few days a week okay so battery well done wont start but some power left have splashed out on fancy new charger has a rejuvenation mode got that on and blinking how long do I leave it on that mode before switching to charge instructions not clear at all many thanks

The rejuvenation mode is just to try and break up the sulphur build up on the plates. Basically what needs to happen is the battery get a massive shock to shake the plates before a charge can be applied.
Most of the chargers with a rejuvenation mode switch to a bulk charge then a trickle as the process is carried out.
If you're not using the vehicle for long periods of time, a trickle charger would be appropriate to use.
As been discussed already a small solar panel will be enough.

My boat can sit for 3 or 4 months without being run. Last boats battery lasted 12 years, then I sold the boat. Current boat 2 years no problem.

I have an isolater switch on the battery box. Perhaps you could fit one to your Rav.

I also have a quick connect plug attached that hangs out of the battery box so that if I haven't used the boat for a bit and then I'm going to be running the battery all day using the livebait tank etc. I just connect my ctek charger the night before as extra insurance.

Originally Posted by 7mm tragic

My boat can sit for 3 or 4 months without being run. Last boats battery lasted 12 years, then I sold the boat. Current boat 2 years no problem.

I have an isolater switch on the battery box. Perhaps you could fit one to your Rav.

I also have a quick connect plug attached that hangs out of the battery box so that if I haven't used the boat for a bit and then I'm going to be running the battery all day using the livebait tank etc. I just connect my ctek charger the night before as extra insurance.

+1 for the isolator switch, I’ve had batteries last up to 16 years in a couple of ‘low use’
vehicles by turning off the negative terminal when they’re not in use.

Originally Posted by Barry the hunter

okay someone clever please my Rav4 every winter battery goes down lack of use having two vehicles does not help as only go about a few days a week okay so battery well done wont start but some power left have splashed out on fancy new charger has a rejuvenation mode got that on and blinking how long do I leave it on that mode before switching to charge instructions not clear at all many thanks

What model/brand of charger? Most with a rejuvenation mode leave it on that for 24 hours then automatically progress to the analysis mode and after that if all good a charge... Cambo has pretty much the right of it there.