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LiPo is not the same chemistry as LiFePO4. LiFePO4 vehicle batteries usually have cell balancing circuitry built in to be a drop in fit for vehicle use. Resting voltage is 12.8 to 13.2 volts on those (3.2 to 3.3 volts per cell), ideal for stressed 12V systems.
Quote:
Originally Posted by ozscott
Hi Scott and sorry mate, but DiscoMick’s post is spot on the money.
And as to your claim that there is a about how alternators charge, well you are correct about the fallacy, but it is the exact opposite of what you are claiming, as Eevo pointed out.
The problems associated with cranking batteries ( and auxiliary batteries ) not being fully charged by an alternator has nothing to do with some fictitious claim that the alternator is the cause, but is actually because the vehicle is not driven long enough after each start.
Adding a DC/DC device to the limited charging time does not resolve the problem, rather than fix the problem, it can actually exacerbate it, if the auxiliary battery is in a low state of charge in the first place.
In this type of situation, you are correct, eventually, the DC/DC device will, after many short drive, bring the auxiliary battery up to a fully charged state, but a Land Rover alternator will have the auxiliary battery fully charge in the same situation but with much few short drives required to do so.
Next, you posted up that “all AGM battery manufacturers 14.7v is the preferred AGM charge voltage”. This is not correct and is also a misunderstanding of what the manufacturers are stating.
The 14.7v quoted, is not the required voltage needed to be able to fully charge the battery, the 14.7v is the MAXIMUM SAFE voltage that “MANY” not all, AGMs can tolerate, above which the battery can be damaged
Unlike your claim that this is for all AGMs, again, Odyssey and Optima batteries are just two AGMs batteries that can be SAFELY charged will voltages in excess of 15v.
I noticed you quoted info from the Optima battery site, but you only picked the sections that supported to your argument. Had you read all the info you would have seen that Optima specifically states “Alternator 13.65 to 15.0 volts, no amperage limit.”
So even if Land Rover alternators worked at a much lower voltage, they would still be within the required charging range of an Optima, which is one of the most common batteries using as an auxiliary battery in Land Rovers.
You also raised the point about having dissimilar batteries. This is another one of these myths used to make people think there is a problem with charging dissimilar batteries at the same time, with an alternator.
If you believe the crap they spin, saying you need to separate batteries to charge them properly. Well this is only the case if you have Lithium auxiliary/house batteries.
But when all the batteries are lead acid the batteries, be it AGMs, Gel, Wet Cell or the new Lead Crystal batteries, alternators charge each battery at it’s optimum charge voltage and current.
And here is a fact for you that most people are unaware of. When charging with a DC/DC device or a battery charger, if you set the maximum voltage to no more than 14.4v, can charge mixed battery types at the same time as well.
There is a lot more to this subject, and while you may be happy with what you have, you do NOT have the optimum charging setup.
But when it comes to the optimum Land Rover dual battery system, there is nothing better than one of my setups, and they cost a lot less than a DC/DC setup yet give far better performance.
Hi Keith and I hope the info above will be of some help to you.Quote:
Originally Posted by 123rover50
Call me when you are ready.
Thanks Drivesafe. I will leave it there and appreciate your detailed arguments. I wasn't being selective buy maybe guilty of not reading the whole article. I know you get passionate about your view of DC to DC versus alternator charging using an isolator on this and other sites which is not a criticism. I really wonder though in our age of people who are quick to litigation or consumer affairs type complaints why major companies like Red Arc are not worried and why there has been no hint of consumer affairs getting involved (as they did with some electronic rust prevention systems). It would be great to get a Red Arc rep to argue the point. As a matter of interest have you contacted their excellent tech dept and asked them why they are selling things that reduce charging rate and battery life compared to an alternator and sought their response. I mean these aren't Brock Polarisers.
Cheers
Easy...
The DCDC systems work as advertised unlike ERP Systems.
On on Vehicles like modern Hilux etc are a solution to a crappy charging system design.
Not necessarily the ultimate, or most cost effective, but they meet a criteria.
Same argument could be had for Land Cruiser "King off the Road" etc. hardly the a true statement [emoji6]
Hi again Scott, the problem is not one product or one company, almost the entire industry operates in the same manor.
The problem is that Australia has some of worst consumer protect services of any modern country.
As far as contacting any company goes, I would rather keep on giving people the correct info and they can then make their own decisions, based on real facts, as to what is going to give them the best results for what they want to do.
Tombie I understand your point however Red Arc were making and selling DC2DC well and truly before modern smart alternators and they talk about AGM batteries needing such devices. Tim no worries people can read your helpful posts and web site info from manufacturers of DC2DC/4WD auto elecs etc and at the end of the day doing the best that they can (as I did) they lay down their hard earned on what they want.
Cheers
It's hard to research accurately out there...
Many seem to present generic / outdated or bias information.
Some present solutions that are effective but not efficient.
Some just take the easy approach (some installs are very forgiving of lower quality installs)
It's a mine field. [emoji41]
Btw - our D2 and D4 reach 12.6v (rested) in a 30 minute drive [emoji6] and that's because of the inrush capability [emoji41]
Hi Tombie and it’s ironic that you should post that up.Quote:
Originally Posted by Tombie
In the middle of last year, when the first of the new Prados arrived, I got a call from two different ex Land Rover owners, who had just purchased new Prados and both wanted to fit a dual battery kit to them.
Neither was all that impressed with having to fit a DC/DC device, as they were recommended to have to do.
They phoned within a week of each other and I explained to both, that I had not had a chance to study the new Toyota alternator operation and as such, did not know if my system would work as required.
Both did not care and offered to test my isolators in their new Prados.
A deal was struck, where if the isolators did not work, they could return them and I would refund the their money in full. all I asked for was that they give me some feedback.
With in a few weeks, both had contacted me and told me their setups were working fine. They were happy and so was I.
One of them posted up his findings on a Prado forum.
Then a short time after this, a guy with new Pardo, fitted with a DC/DC device to charge his Optima Yellowtop, posted up that but while the DC/DC device was looking after his optima, but because of his short diving usage of his Prado, his cranking battery was around the 12.25 12.4v each morning before starting. Thats 60% to 80% SoC
He posted up some enquiries about my isolators and we came to an arrangement where he would test one of my isolators in his Prado.
Over the past 6 months he had been monitoring both of his batteries, so this would be a good test to see how my isolator compared with his DC/DC device.
Again, still with a limited knowledge of how the new Prado alternators worked, I guestimated that he would probably see an improvement in rested state of his cranking battery in about two to three weeks.
After a couple of weeks, his cranking battery’s rested voltage was 12.5v to 12.65v and this is 90% to over 95%.
He was also very happy with the short recharge times after he used his Optima.
He has since had the opportunity to see how my isolator improves his usage while camping and he was ecstatic at the improvement he got over the way the DC/DC device worked.
The point here is that even low operating voltage vehicles like the new Toyotas are benefiting from my gear in ways no DC/DC device can offer, so with the higher average voltages that all Land Rovers operate at, there is just no reason for fitting a DC/DC device in any Land Rover.
I am also conducting tests in the new Tiguan, which has Stop/Start function plus the alternator turns off when accelerating, and I now have quite a few Amaroks fitted with my isolators.
Not only are the auxiliary batteries charging well in these vehicles, but the reverse charging feature my systems give, means that the vehicle’s own operating systems are benefitting from having my setup in them.
This means as new Land Rovers come out with similar Stop/Start operations, again, my isolators will give benefits no DC/DC device has a hope of achieving. And note I already have a couple of new Range Rover Sports fitted with my isolators and all is working well.
Sorry that is not correct. Not only did both Land Rover ( first ) and Toyota ( a few years later ) have Smart alternators for years before Redarc had their first DC/DC device, a number of other vehicle makes, like Nissan, also had introduced Smart Alternators before this.Quote:
Originally Posted by ozscott
As for DC/DC sellers saying you need a DC/DC device to charge an AGM properly. Try reading the info from the REAL battery experts, the battery manufactures themselves, and see how their info differs from that supplied by people trying to sell you something you never needed in the first place.