The 150 series Dual Battery Guide

[krypto]

Inner guard is more secure and better practice.

[foxpro]

For people who have installed the Sidewinder DBi-140. What is the best location for it? The manual recommends drilled and screwed onto the inner guard but I have seen pictures somewhere with it being mounted on top of the plastic fuse box.

[foxpro]

I
Main battery
Its silly not to replace your main battery IMO.

It might start with the Marine Pro 620 as aux and drop in a new starter should I feel the need to.

Yesterday I have wired up the Sidewinder rear connection and DC panel in the bottle jack door. Looks neat and did not require any holes to be drilled through plastic except for the bottle jack door now being a dedicated power panel.

[foxpro]

If you decide to go with an AGM and intending to charge of the alternator, make sure it can tolerate
high inrush currents and under bonnet temperatures.

I have got a thermal sleeve for the aux battery and for the rest just hope that the battery is up for it.

[foxpro]

mjrandom
Putting the aux inside the car makes sense but I'm cramming for space so the only logical solution for me was under the bonnet. My goal is to set the Prado up as a tourer fit to take three adults around Australia w/o a trailer. It will have a customized cargo area with only three seats remaining.

[foxpro]

LeighW
I value your insights. I'm not really worried about cracking guards. It was a point to consider but as I want a second battery anyway I have to take this route and trust Toyota has this issue under control now. From what I gathered from this thread battery space is restricted to about 260mm wide aux batteries b/c of the aircon pipe although some squeezed larger units in by either bending the aircon pipe or living with cramped interior. TJM apparently has a special tray for Prado 2014 GX's now which allows 305mm batteries. I will check space again when my el cheapo unit arrives from ebay.

I got the point of not swapping aux and starter battery. Thanks for the advice. I don't consider this further.

[MelbournePark]

foxpro,
... overseas models most likely have the starter battery on the right side, some
of the display Grandes when they first come out had factory batteries fitted to both sides.
...

The overseas Prados use both batteries for starting. They do this because of European winters, where it can require lots of battery to start a diesel. -25C is not uncommon in Berlin. Some Prados are also now assembled in Russia, and lots of the East can be colder than Berlin.

i checked this out some time ago, and found the battery replacements recommended weighed close to 22kg.

[MelbournePark]

As far as publishing data, you've mentioned Optima brand a lot. Could you publish their discharge graphs here?

As far as solar goes for Fox - yep, its a complex field, and really much dependent on how long he's camping, and for what periods. Solar - there's a 50% difference from cloud to sunny. And with fridges, there's a big difference from frozen compared to 5C, and from warm weather compared to stinking hot. 240 watts of solar cost some, and then you have to get it into the battery, with the vagaries of the weather too.

Incidentally as far as using the motor - I would like to add the comment not to run a diesel stationary for charging please. Our Prado diesel engines are not designed for that.

As far as DC - DC units and all the rest, and even the voltage of solar units (some are said to be only 17) everything has to be checked out. No need for Fox to do that though - he's doesn't want to spend much, he made that clear. So solar is out. IMO the longer one (ie Fox or myself) delays solar the better, because its cost is dropping all the time. These thin film solars appeal to me too due to their size and weight and evidently their efficiency - but for their current cost.

As far as alternative batteries, its worthwhile for Fox to consider some choices. I think weekend camping and a few longer trips per year, one doesn't need to invest in the best cycling long life system. I do think though that a real cycling battery - rather than a marine style - is worth considering for the spare battery if its usage is considered. A problem though with such batteries, is that they do tend to take up power slowly, due to their heavier plates and that may not suit Fox. I'll check my database too.

I'd like to publish some notes too on battery longevity published by manufacturers, but perhaps when this site calms down. Its interesting to read what the manufacturers say about such things IMO. When I do I'll post the linkages so people can read the sources.

The restrictions for Prado users though for the second battery in the front is probably 260mm and not over 24kg - at least for Fox. The 620 at 260mm and 18.11kg and 75AH seems a safe low cost bet if the Marine style suits his usage.

And by the way, the weights for the Marine Pros were not from the current website, which is wrong. I spoke to Century and the weight of the 620 is 18.11kg, which makes sense. Sometime their website will be updated.

[MelbournePark]

MelbournePark,

When you say an AGM will charge faster what AGM are you actually referring to?

A lot of AGM"s have quite low maximum recharge rates, ones that can accept high
recharge rates state around 3 hours to fully charge.

I have done extensive testing with MarinePros and they will charge from around 50% SOC
to fully charged in around 120 minutes and have hard data to support it. If your referring to an Optima it is not a typical AGM deep cycle battery, it was specifically designed for rapid recharging off an alternator?

Can you supply some model numbers and link to data sheets?

What would be the advantage in a DCDC charger in the above install, it will slow recharge times considerably unless a 40A or higher unit is installed and then more or less match the alternator?

If you look at it from the solar side, none of the current crop of combo units have very efficient mppt controllers built in, granted if your on a tight budget and not worried about efficiency or redundancy they could be a good choice, but if you want maximum efficiency out of your panels a good quality mppt charger would be a better choice?

They all need to be checked before buying. I'm not going to publish all the batteries with their stats here. Its buyer beware.

As far as the Marine Pro quick charging, does the 620 charge in the same time as the 730 in a dual setup?

You've said you have a Marine Pro as your starter, and an Optima as your spare. You've also said that the Optima charges very quickly. I presume you are running a D34 for the spare, with a 720 as your starter battery?

I also think charge depends on what style of camping / touring your going to do. If you're an itinerant / nomad like I tend to be - and go from place to place every day or two - then IMO a fast take-up battery makes a lot more sense.

Another issue is the amperage available. Lets hope that the Prado with your volt enhancer equipped has an excess of 60 amps after it runs its air con, thermostats, radars and smarts and computers and network et, sat navs, ABS and crawls and all the other stuff. That means with two batteries receiving charge, they'd have 30 amps available for each. So I think that in that case, an AGM with a 30 amp input capacity, is all you need.

And if you had a 10 amp accepting main battery, then would a higher accepting AGM be a benefit? Perhaps not if the starting battery played a major game in providing power.

For instance, if you had a 730 with 100 amps as your main battery, it would likely have 50 amps to be re-charged. If that took two hours, then what would be the point in having an AGM that would charge its own amount (a D34 with 60% to recover would require only 33 AH to recover). But the real main issue would be recovering the 50 amps from the slower accepting Marine Pro 730. Therefor - its more sensible to have two marine Pros and save the money. Why have a fast recovering on the second battery when one half the cost will match the main battery's re-charge?

Likewise for any other battery. Add a trailer onto the back of the Prado with a couple of batteries in the trailer, and the benefits of 30 amp accepting batteries in the vehicle would diminish. Ultimately its about the bottlenecks IMO. I'll post a couple of batteries that appealed to me a later on, in another post.

I'll finish this post here - its gone too long. Apologies to all.

[mjrandom]

foxpro,

It is not practical to swap the batteries around, the sense point for the alternator voltage regulator
in the Prado is the main fuse box, if you extended the battery connection cables to the passenger
side you'll affect both the charge voltage and available starter current, both guards would have more
or less the same rating, overseas models most likely have the starter battery on the right side, some
of the display Grandes when they first come out had factory batteries fitted to both sides.

If you decide to go with an AGM and intending to charge of the alternator, make sure it can tolerate
high inrush currents and under bonnet temperatures.

For what it is worth I agree 100% with Leigh, just not worth the trouble of swapping the starter battery around. If you want more AH out of the aux then go AGM and put it in the back. That is what I did.

[LeighW]

MelbournePark,

When you say an AGM will charge faster what AGM are you actually referring to?

A lot of AGM"s have quite low maximum recharge rates, ones that can accept high
recharge rates state around 3 hours to fully charge.

I have done extensive testing with MarinePros and they will charge from around 50% SOC
to fully charged in around 120 minutes and have hard data to support it. If your referring to an Optima it is not a typical AGM deep cycle battery, it was specifically designed for rapid recharging off an alternator?

Can you supply some model numbers and link to data sheets?

What would be the advantage in a DCDC charger in the above install, it will slow recharge times considerably unless a 40A or higher unit is installed and then more or less match the alternator?

If you look at it from the solar side, none of the current crop of combo units have very efficient mppt controllers built in, granted if your on a tight budget and not worried about efficiency or redundancy they could be a good choice, but if you want maximum efficiency out of your panels a good quality mppt charger would be a better choice?

[LeighW]

foxpro,

It is not practical to swap the batteries around, the sense point for the alternator voltage regulator
in the Prado is the main fuse box, if you extended the battery connection cables to the passenger
side you'll affect both the charge voltage and available starter current, both guards would have more
or less the same rating, overseas models most likely have the starter battery on the right side, some
of the display Grandes when they first come out had factory batteries fitted to both sides.

If you decide to go with an AGM and intending to charge of the alternator, make sure it can tolerate
high inrush currents and under bonnet temperatures.

[MelbournePark]

Wow, after reading many pages of this informative thread on what I thought to be a straight forward task I still have some questions.

I'm after the simplest DBS solution possible. No bells. No whistles. No dash display. No switches. Just two outlets in the back. One to power a 40L fridge. One for compressor/general usage.

I have so far ordered:
- ebay battery tray
- Sidewinder Battery Isolator Kit & Cable Set
- Sidewinder Rear Power Outlet cable
- BAINTECH DC Distribution Panel BTCP004R - Volt, USB, CIGA, CIGA 20A Circuit Protect
- Marine Pro battery NS70M (MP620) probaly

My questions:

- Should the starter battery run flat, can simple existing starter cables be used to link the two batteries and hopefully start the engine? Or would that upset the isolator? I would prefer this instead of wiring the link switch. Every part that is not installed can not fail or malfunction.

- Contemplating switching Aux/main battery to allow for a larger Aux in the factory position. Are there still issues in regards of too much weight and possible inner guard cracks in 2014 models?

Issues in the 2014 seem totally gone.

Even my early 2013 had a different guard part number.

Note that many say you should connect the top of the battery metal retaining bar to the body work as well - to eliminate the top of the battery weight swinging on its base, hence making the battery base move upon the guard. Makes sense to me. On corrugations many say say check the tyre pressures to provide a smooth ride, and travel at a smooth speed. So people say ...and some say a rubber base for the battery is good for the battery.

On your kit and battery selection:

The starter battery won't run flat because the Sidewinder DBi-140 automatically isolates the starter battery when it gets down to 12.4 volts. The Sidewinder also allows 400 amp twin battery start, but that might not be likely because the main battery will be protected.

Your likely to order the Marine Pro 620 battery for the spare space. Its dimensions and characteristics are as follows:
Weight 18.11kg
Length (Across towards the air con pipe): 260
Width: 171
Height inc terminals: 202
Reserve Capacity: 155
AMP Hours: 75
Weight: 18.11kg
Current Cost: $175

Its length should have it right on the compressor tube. There are narrower choices, but this size has made many fit without any hassles. The weight is below Toyota's supplied batteries, which weigh about 22kg ( I say supplied because in Europe they supply two and I checked such battery weights and they were over 21kg but a bit under 22kg).

Main battery
Its silly not to replace your main battery IMO.

Firstly - the Sidewinder DBi-140 is designed to use the starter battery for auxiliarly power, and then stop the flow of power when it reaches 12.4v. However if its just a starting battery, that constant use will screw the starter battery, because its not designed for such cycling use.

The obvious choice is the Marine Pro 730, which costs $20 more.
Key differences are that it:
Weighs 6kg more than the 620 ie 33% more at 24.17 kg,
AMP Hours: 33% more at 100 AH
Is longer at 306mm, but it will fit in the main battery slot. Ensure that its top is also located to the body work.

Total battery cost would be $370, for lots of AH, and the isolator will keep the bigger 730 safe for starting.

Downside on the Marine Pro is slower re-charge than AGM.

But an AGM like the Optima D34 would cost $300, and weigh 19.6kg, and provide 55 AH.

While a twin Marine Pro (730 starter and 620 spare slot) you'd get 75AH for the 620. How much for the 730? Well, 12.2 volts is about 50% load on the 730. So the cut off is set at 12.4 volts, so that means perhaps 55% of the capacity of the 730 without much harming its life. That means 55AH extra. Ideally you would only run the 620 to 50% ie 12.2 volts, because it would last longer. ie use 37 of its AH. But treat as LeighW says, the spare as a consumable, and although it won't last as long, the good news is that the starter will last for quite a few years.

The other way is to incorporate a DC : DC charger which can also input solar cell power into the reserve battery. That gets more complicated, costly (much due to the solar) but for long stays is a good plan too - as others have often done here.

[LeighW]

foxpro,

Just keep in mind it's no good using a small battery to reduce weight if it is not
going to have enough Ah to keep the fridge running, if your that worried about guard
cracking then maybe look at putting the battery in the rear of the vehicle instead?

[MelbournePark]

...
I don't believe there is a conspiracy in the battery industry to keep them out, they have also seen other battery types come and go that were going to make everything else obsolete and it didn't happen due to their shortfalls. Their not going to going to start down a road a possible loose many, many millions of dollars until a technology has proven itself.

Simple fact is other battery technologies to date just haven't performed as per the manufacturers glossies, current generation lithiums maybe be different but the first generation self destructing and causing fires hasn't been all that successful requiring a second generation.

My view is that current Lithium Fe batteries are not a second generation because they are a significantly different compound with less efficiency and are non volatile. IMO a different thing altogether.

They are now universal in motor racing, even in the now hybrid F1 cars, where spectacular disintegration of vehicles is expected but the Lithium batteries have survived without issues.

As far as generational changes, they are happening in Lithium Fe batteries, in the control interface issues. There'll be a race for the best version, lots of different brand choices, and improvements into further generational products. I'd say the internal electronics and cellular designs are justified to be termed second generation from my strategic perspective, but an expert in batteries might call me out on that.

We've all discussed which battery to put in our Prados, and outside of the expensive Lithium, the choice is between a "Flooded" marine style/rugged flooded cycling type, or an AGM.

The point about all those, is its all old technology. The innovations in lead acid have been incremental, and based on less owner intervention and less leakages, easier shipment and longer shelf life. All mostly cost saving, logistic improvements rather than technological improvements. Glass does decrease charge times too. It's a very mature industry, and the dominant cost of a lead acid battery is the amount of lead in it, its distribution model and its marketing. I don't believe AGM costs much more to manufacture either - its just that AGM batteries are aimed at higher quality markets and hence they have more lead in them which increases their cost. By the way, my base is mostly manufacturing, also strategy and banking & finance.

Battery companies go broke all the time, and production is moving to low cost countries. So many are now made in China and Asia. LifeLine - a USA company, is family owned, and still operates in the USA. But such businesses can't be easy, and LifeLine is just a small niche quality player. There's little value added left in the lead acid battery business. Johnson spends a fortune on marketing them.

Johnson have bought lots of battery companies in their conglomerate expansion, and have put Optima on a Cash Cow pedestal via advertising while lowering Optima production costs a bit by shifting their whole Optima plant from the USA to Mexico. Those with long lived Optimas have the made in USA sticker on them, a sticker that has now gone. Johnson's Varta is a huge brand in Europe, its not popular here, probably because Johnson's marketing department just made that brand recognition choice.

Meanwhile the USA battery operation might well be focusing on added value. Hence Johnson's forthcoming and announced Lithium batteries are not far away.

As others have posted here, you can buy two batteries just the same, with a different label on them, and totally different prices here. And even with the same label prices can vary hugely. Marketing and distribution plays a huge role in the battery business.

Price differences are not so easy to find with Optimas, because they are a heavily marketed differentiated product, and the secret to that model working is avoiding significant discounting. The good news with Optima is you cannot easily copy them due to their design, unlike Trojen's excellent quality batteries, which are often copied and put into counterfeit red/brown cases by companies in China.

In contrast, Lithium is new technology. It's off the bottom of its learning curve, but its growth is predicted, and its going to be huge. 12% per annum, and sourcing Lithium - which was once of no interest to all but some lubrication grease producers and the nuclear industry - is now a big thing.

Just sit back and watch it grow. If light weight matters, as Lithium matures it'll take over, if not in volume then certainly in profits! And a quote from 2012:

"Galves says that lithium-ion batteries for electric cars cost about $600 a kilowatt-hour, compared to $250 a kilowatt-hour for laptop batteries. “There’s no reason automotive batteries can’t get that low,” he says" http://www.technologyreview.com/news...makers/page/2/

A footnote: the Tesla car uses Panasonic Lithium Fe batteries, is high performance, and has a range of I think 270 miles, yet can be re-charged in 20 to 30 minutes!!