Smart chargers

[flatfloor 3.8]

Hi, does anyone have any recommendations or advice regarding "smart battery chargers/conditioners.
Thank you
Bill

[rswaffie]

I’ve used the CTek chargers for years, both for modern and classic cars. Do the job with no fuss.

https://www.ctek.com/uk/

[christopher storey]

Another unhesitating recommendation for the CTeks - get a bigger i.e. 10 amp rather than a smaller one

[dlgis]

I’ve got 3 cars on 3 different makes of trickle charger at the mo, they all work fine. The E type is on a Ctek 5.0 that I bought 2 years ago and works perfectly. About £80 on Amazon, £65 on ebay. Might be some deals on Black Friday if you can wait

[malcolm]

I use a 20 year old optimate on the E Type, and a Ctek on the F Type. Both are fantastic.

[mgcjag]

Are we talking about just to charge the battery....or to leave it connected over winter?..never had a need personally to leave one connected..Steve PS.. I do always use an isolator switch it disconnect the battery

[paydase]

During winter or when the car is not driven for (a) month(s), it is useful to recharge the battery occasionally (e.g. 1/month) or to keep it permanently on a charger.
This is especially recommended if the ground terminal cannot be disconnected.
It prolongs the battery life, avoiding deep charge/discharge cycles that wear the battery.

An alternative is of course to disconnect the battery terminal. The discharge of the battery is then much slowed down, allowing long periods of non use, but it still discharges...
As an indication, battery sellers recommend that their batteries be recharged someting like once every 6 months if staying unsold in the shelf.

Concerning the capacity of the charger, I use the regular Ctek 5, even for a big 100 Ah battery of one of my cars, and I found out that it has worked unflawlessly for years.
The Ctek 10 is much more expensive...

[MarekH]

I have a Halfords charger. I hooked it up to a voltmeter and ammeter to see what it was doing. Essentially it starts by "hunting" for a charge voltage where it can put full charge (a lowly ~4amps or maybe less iirc) and then slowly zig-zags up and down a bit but this is superimposed over a staircase function. It maintains a charge voltage about 1.5volts above the battery's voltage and cuts off when it reaches ~14.6volts. There is obviously an algorithm in there (or some primitive monitoring via resistors) which look at whether the small upward zigs or the downward zags on each "stair" lead to a higher or not state of charge and it slowly ups the voltage accordingly. The charging current is also limited. There are two modes - one for standard lead/acid batteries and one for gel batteries. There is also a switch for large versus small batteries. The small battery mode runs a lower current than the large battery mode and lets you further charge a large battery, albeit slowly, after the large battery was deemed fully charged. Like other smart chargers, a battery deemed fully charged is allowed to discharge and then topped up accordingly.

It seems to work perfectly well with an Optima Red Top.

I'd guess the differentiating factor with these chargers is whether they have some additional strategy for deeply discharged batteries or not. I haven't analysed any other smart chargers other than this one, so am unable to add more.

kind regards
Marek

[SESH]

I have always used CTEK mainly the MXS 5.0 and it has always worked well. But I read an article recently in one of the motoring magazines that the Ring 8 amp trickle charger was good value. They do other lower amp models too at lower prices.
Mike

[malcolm]

I'd guess the differentiating factor with these chargers is whether they have some additional strategy for deeply discharged batteries or not. I haven't analysed any other smart chargers other than this one, so am unable to add more.

kind regards
Marek

My post on this seemed to disappear! The Ctek and Optimate do have a restore function for deeply discharged batteries.
If they sense both a very low state of charge, and a battery that isn't taking the expected charge levels, they go into desulphate mode. A very high voltage is sent in very brief bursts. The battery is then charged normally. All this is done automatically. I've resurrected a few seemingly dead batteries with these.

The Ctek also has a long store mode. Automatically, afterabout 10 days, it maintains the battery at 95% rather than 100% so it isn't permanently adding charge.

I've used these on famously weak batteries on sports motorbikes, where a tiny battery is trying to turn over a big lump. More than 2 years life is good - mine lasted 15 years.

My last E type battery also lasted more than 15 years. (The date was stamped on it when I bought the car!)

[christopher storey]

<alcolm : one point anyone trying to charge a very flat battery with a CTek needs to know is that they will not charge if the battery voltage is below 2 volts . So, if that situation arises, you need to connect a normal charger to the battery to bring the voltage up . IIRC, you can connect an ordinary charger , and then connect the CTek in parallel, without waiting for the battery voltage itself to rise

[mgcjag]

Hi Christopher....not so smart these modern units..as you say you still need an "old school" charger to charge a flat battery

[malcolm]

I’m sure you’re correct Christopher (as usual!) but if a 12 volt lead acid battery gets to less than 2 volts, isn’t it dead?

[mgcjag]

Hi Malcom...leave you lights on..it will drain your battery....the "modern" type charger i have wont charge it back up...the old school unit will....Steve

[christopher storey]

Malcolm : no the CTek will revive almost anything, but its circuitry requires if to encounter a residual voltage of 2 volts . If your car is gradually discharging the battery ( immobilisers are one of the prime sources of this ) - Both my Bentley Continental R and my Mercedes CLK do it - it will easily go down to 2 volts within perhaps 3 to 4 weeks

[flatfloor 3.8]

Well it looks like its the CTEK that will be in my Christmas stocking. Thanks to everyone for all the advice.

[malcolm]

Malcolm : no the CTek will revive almost anything, but its circuitry requires if to encounter a residual voltage of 2 volts . If your car is gradually discharging the battery ( immobilisers are one of the prime sources of this ) - Both my Bentley Continental R and my Mercedes CLK do it - it will easily go down to 2 volts within perhaps 3 to 4 weeks

Thanks! Interesting

[PierreW]

Not really an "smart charger" but allows you to maintain the battery charge during periods of immobility such as during winter, I have used 4 without any problem for years...
https://fr.aliexpress.com/item/10050060 ... 2fc20632ac

[PierreW]

I forgot to say that it regulates the voltage to 13.7 v at the end of charging.
Pierre

[rfs1957]

I've used CTEK 0.8's for 10+ years to keep the Mini and the Jag on a permanent drip-feed.

Both run Advanced Glass Mat batteries.

I use banana-plugs and sockets, with an in-line fuse on the car side.



Wheel arch for the Mini.



LH under-tray on the Jag.



True, I don't drive much in the rain ........