I’ve just replaced the battery on my 2007 MX5 as it kept going flat - I don’t use the car very often.
Please could somebody recommend the necessary parameters (wattage etc) for the correct battery conditioner? Thanks in anticipation…
Ian
Short answer:
The “power” rating of the conditioner doesn’t matter. This is because if the battery is “maintained” then the conditioner has almost no “work” to keep it charged. As an example it might be left permanently connected and kick in only once a week for a few minutes to top it up. Also the brand isn’t too important and doesn’t need to be from the motor manufacturer.
Longer answer:
There is a difference between a regular (cheap) battery charger e.g. one that you might have bought and stored in a garage hoping never to need it and a maintenance charger.
These cheap chargers are simply a low voltage transformer and a rectifier. The circuit produces a “DC” (one direction) current (of sorts) and charges the battery. This “works” until the battery is charged and then you have a “problem” because the voltage on the battery continues to increase and the battery boils off the electrolyte and eventually the battery needs replacing. So you have to monitor it and then disconnect and then use again - see the problem?
A maintenance charger works a little differently. It charges the battery using 3-6 different charging methods e.g. constant voltage, constant current and finally it stops. All batteries will discharge slowly and the charger continues to monitor the voltage. As needed it switches on and trickle charges the battery. The cycle repeats. At this point the “work” is minimal so almost any charger will work e.g. it could be a “12V 1A” or “12V 4A” charger - makes no difference.
As an example, some car manufacturers sell a charger for their vehicle that’s only 1A. Or for a bike only 0.5A. This “works” because the charger has almost no work to do because it’s normally left connected. Just more profit for them.
An interesting alternative is a solar charger - you can buy these from Halfords and they plug into the car’s aux connector. They charge the battery using sun light - obviously won’t work if the car is garaged. A car charger wouldn’t be an option if you didn’t have continuous power e.g. parking on a public street. So both types have their uses. Most solar chargers don’t have any form of regulation - so like a cheap charger they continue to charge the battery. Generally this is OK because the charger is pretty feeble so it only manages to top the battery up. In theory it could damage it.
I recommend a maintenance charger from a company like CTEK (see below) - they can be bought from Amazon for about £30-60 and considering the cost of a battery and the inconvenience of a flat battery they are a great idea especially as letting a battery go flat more than once/twice generally wrecks the longevity of the battery. The same charger could be used to charge a second vehicle and also a bike if required. They can switch between 6V and 12V as required. (One is higher current than the other but as discussed it really doesn’t matter).
The bigger one can be used to “jump start” or put sufficient power into a “dead” battery to allow the car to be started in 30 minutes (theory). Actually not a good idea unless you then drive for a while to complete the charging using the car and probably more stressful full than a proper charge.
Of course if the battery is “flat” then a 1A charger takes longer than a 4A charger to restore a battery to full charge. Since a battery is unlikely to ever reach this point then it’s not relevant. It just makes sense to buy something around a 4A charger from a good make for a car and a 1A charger for a bike. More important are the type of leads supplied and the “system” they use e.g. buy another connector for another vehicle and you can charge two cars for almost the price of one.
There are less expensive chargers available but if you left a charger connected for months on end in a garage would you feel comfortable with a “cheap” or a “quality” product e.g. whilst you were away on holiday? With a good charger and regular use the battery easily lasts it’s designed life which might otherwise be cut short by not maintaining it/driving regularly.
Simon
PS you might want to think how will it be connected e.g. battery terminals wired to a connector. Connect as required. If you have an aux connector that is permanently connected then a plug in connector is better especially if the lead then passes between the door seal and the door.
A C-tek charger is a good idea.Take a look here;https://www.amazon.co.uk/s/?ie=UTF8&keywords=ctek+battery+charger&tag=mh0a9-21&index=aps&hvadid=2978703817&hvqmt=e&hvbmt=be&hvdev=c&ref=pd_sl_3la2u7m3el_e
Or an Optimate 4, as recommended by me and four other owner/users in the family! Up to 70Ah and are used on MX5 ND, Peugeot Camper, Honda Civic, Honda Jazz, VW Golf, plus Honda & Yamaha (BIG) bikes!
PS: If you want up to 240Ah you can always get the Optimate 6!
They are another good brand. The Optimate 4 “targets” bikes, however this one (more expensive) is for cars e.g. for a 75AH battery:
Actually, anything is better than nothing (and will work just fine).
Simon
They are basically a case, a transformer and rectifer attached to a micro processor with some leads.
End of storey!
The items recommmended above are expensive as they are heavily advertised and sold through dealers who also take a mark up and are no better at all than the cheaper brands.
Keep your eye on Lidl and Aldi as they both sell them twice a year at around £15 a unit.
I have had the units from both Lidl and Aldi for around 5 years and they are still working so the more expensive units appear to be no more reliable.
The problem with both Lidl and Aldi versions is, as you’ve pointed out, they’re not always available, the stores are not necessarily near to hand and they don’t do mail order!
I would be astounded if the Aldi/Lidl charger is as good as the Optimate 4.
Great value at £15 though. Once I understood how the Optimate 4 worked I realised how much better it was that the old Optimate 3 which I also own(10 years+) and still use. Strangle that no-one on this forum and even the supplier could advise me at the time but to be fair the thread was probably on here a year ago.
Another thing to consider is that your 2007 MK3 has a panasonic battery but it is lead acid rather than the AGM(absorbent glass mat) fitted as standard to the MK1 - MK2.5 cars.
In real terms this is likely to mean that the battery will not last anything like as long as the AGM batteries do. If yours is a 10 year old original battery it will need replacing soon.
Panasonic are a great brand of battery but everything runs out of useful life eventually.
The LIDL and Aldi versions get mixed reviews e.g. some people think they work, others that they don’t or that they break quickly. This could be because some people ask them to recover a completely dead battery and then blame the product if it doesn’t work miracles. One of these brands had a charger available (usually for a week) that had a faulty button - the instructions excluded the button from any guarantee - but then what do you expect from a tenner?
I found this “review” helpful and I do have one of the older CTEK units bought 10-15 years ago and still perfect for the task.
https://www.amazon.co.uk/gp/aw/cr/rR1THU0OHIH12W9
NB I agree that some of the claims made are a little lacking by some brands. There is some science to doing charging optimally and not all companies do it right. The really cheap battery chargers are really nasty and don’t do anything for the battery. Like most things YMMV so be careful.
Simon
I have used an Optimate for several years, no problems at all