Lithium Battery & Traxide DBS

[rocket rod]

Howdy All. I'm toying with the idea of adding a lithium battery to the mix in my car. Currently I have a Traxide system with Optima yellow top in the front. What I'm thinking is to add a slim lithium to the space were the 3rd row would normally go. I have a 5 seater and under the floor is a foam cut out for the tool kit/jack etc and there if plenty of room (I think) for a slim battery. One battery supplier in Perth advertises that his lithium batteries don't require any changes to your existing charging system. It's a drop in replacement. 120AH 12 Volt Lithium Battery iTECH120 | iTechworld (https://itechworld.com.au/collections/lithium-batteries/products/120ah-12-volt-lithium-battery). This particular battery won't fit but what if he did a slim version that did? I could hook it up to my Traxide system and there you go. Or could I?

[DiscoMick]

I'm sure Drivesafe and others could explain this much better, but I understood lithiums need a DC-DC charger because they require 14.7 volts to fully charge. Is that right gurus?

[gavinwibrow]

I'm sure Drivesafe and others could explain this much better, but I understood lithiums need a DC-DC charger because they require 14.7 volts to fully charge. Is that right gurus?


Normally neesd something, but according to their advertising blurb, iTech have built in BMS which means they can be just dropped in providing they will fit?

Doesn't solve your issue if you can't fit an iTech version though.

[W&KO]

Interesting, especially if it’s truly a drop in and one doesn’t need a DC-DC upgrade.

They mention it’s the only lithium battery suitable for inverters, would have thought plenty would have an inverter hanging off their lithium’s.

[Geedublya]

The big problem is that lithium batteries don’t have voltage drop as they discharge. So the traxide won’t isolate the battery until it is too late.

[AK83]

IIRC some lithiums require 17v to charge properly.
But there are many of these iTech types that have internal BMS systems in place(inside the casing), where they convert the 14.something volt input to the required voltage for the actual lithium cells.
The cells used are most likely to be 16850 types too.
So the internal BMS does all the input and output work.

[W&KO]

I sent off a couple of question to see if my setup (not traxide) is suitable for drop in.

[drivesafe]

Goodmorning folks, and first off, as I sell lithium batteries, I need to make this clear before I start going through the questions above.


First and foremost, you need to google questions about the "reliability" of the info put out by iTechworld. They seem to suffer from supplying "misinformation" ( I'm being polite ) and have a habit of continually changing the specs for their different products sold.


That aside, over the passed 7 years, I have been carrying out extensive testing of different lithium batteries supplied to my by a company that was interested in supplying the then new type of batteries to the trade.


The cheap cells were not available back then and I have never had ( nor wanted ) the chance to test them. And in the couple of years the cheaper cells have been available, at least two companies/brands selling them are no long in business and you can come to your own conclusions about that.


As to the claim they are “the only Lithium battery suitable for inverter use” is pure B/S, because one of the primary reasons for using any good quality lithium batteries in RV situations, is that a much smaller lithium battery can safely supply a much large current capacity over what a lead acid battery can supply to power the large inverters that are now common lace in the RV industry.


One of the tests I regularly carry out, is to place excessively high discharge loads on the different lithium batteries I test, to see what they will tolerate beyond the manufacturer’s actual recommended operating specs.


On a number of occasions I have placed discharge loads on lithium batteries to 400% ( 4x ) of the batteries marked Ah and this was not just for a short period of time but from a fully charged state till the battery’s BMS shut down, only once did I damage a battery do this and even then this only occurred after the battery had been subjected to more than 25 charge/high current discharge cycles.

The advertised maximum of those batteries is 280, is this their MAXIMUM Continuous or PEAK discharge current. It does not say.

Their continuous discharge current is listed at 100 amps frothier 120Ah battery and mine has the same for a 100Ah battery but will safely supply 160 amps continuously for periodical use, such as that when used in RV situations.


The batteries I am now supplying are rated at 100Ah and so far, I have not tested one for them where the available capacity did not exceed 104Ah, and on average it has been 108Ah.


There is no mention of just how much capacity is actually available and as many Lithium batteries are marked similarly to lead acid batteries, where the true amount available is actually around 80 to 90% of the marked size, needs clarification.


As for any lithium being a drop-in replacement, yes you can do this with most lithium batteries, ( not in an engine bay ) but they will not be able to be charged to their maximum capacity without controlled charging, and this is actually something you can only do while NOT driving ( take a lot of charge time to achieve a fully charged state ).


And the real problem, as pointed out by Geedublya, lithium batteries need to be independently separated from lead acid batteries once the motor is turned off.


This is because lithium batteries sit from 13.2v to as high as 13.8v, with no load and no automotive isolator will do this.


While keeping the lithiums connected to lead acid batteries once the motor is off, would actually be very good for lead acid batteries, the continual discharging of the lithium battery would be both a waste of energy and would most likely have a major effect on a lithium batteries lifespan.

[drivesafe]

BTW, of all the RV/Automotive type lithium batteries I have worked with, the MAXIMUM safe charge voltage is 14.8v and the reference to 17v would be for non automotive type lithium batteries, like those found in battery powered tools.

When you buy a lithium battery for RV use, regardless of brand, make sure you know the maximum charge voltages for your specific brand of lithium battery and do not exceed this level.

[rocket rod]

Perhaps I'll go out and buy a can of worms instead. I think it will be simpler?

One thing that I haven't put to the test fully is a recently purchased Projecta folding 120W solar blanket to see if that can keep up with the camp power generation duties. On this issue and I know I'm hijacking my own thread but, has anyone swapped out the PWM controller that comes with the blanket for a MPPT type and if so what improvement did you notice?

[W&KO]

Perhaps I'll go out and buy a can of worms instead. I think it will be simpler?

One thing that I haven't put to the test fully is a recently purchased Projecta folding 120W solar blanket to see if that can keep up with the camp power generation duties. On this issue and I know I'm hijacking my own thread but, has anyone swapped out the PWM controller that comes with the blanket for a MPPT type and if so what improvement did you notice?

I removed the original regulator and plug via Anderson Plug into a 75/15 Victron, mainly as it’s already permanently fitted next to AUX battery.

It seems MPPT is the go these days....but I haven’t tested the two side by side.

I my work car I have a PWM which works just fine.

Everybody loves a pic....

https://uploads.tapatalk-cdn.com/20191127/fb8ebadf0a853379d13cd9fb6f6265cc.jpg

[DiscoMick]

My BIL is quite impressed with his recently purchased Korr MPPT regulator, but his panels are different to yours.

[Redtail]

Perhaps I'll go out and buy a can of worms instead. I think it will be simpler?

One thing that I haven't put to the test fully is a recently purchased Projecta folding 120W solar blanket to see if that can keep up with the camp power generation duties. On this issue and I know I'm hijacking my own thread but, has anyone swapped out the PWM controller that comes with the blanket for a MPPT type and if so what improvement did you notice?

I can't give you a comparison, but when I set up my system (Traxide/Optima) about 18 moths ago, I bought a 120W folding "blanket" charger from JayCar and never bothered with the PWM that came with it. Having done a lot of research via reading and talking to outfitters, I went straight to a Victron MPPT and just have the PWM as an emergency spare. I figured if the el-cheapo folding panel ever fails, or as solar panels become more efficient, I'll always have a quality and very efficient regulator.

[DiscoMick]

I find my Kings 200 watt folding blanket never goes even close to the 15 amp limit of the PWM regulator. If the battery is flat I can just plug it straight to the battery. But just have to remember to disconnect before the battery is fully charged or it will cook.

[rocket rod]

I can't give you a comparison, but when I set up my system (Traxide/Optima) about 18 moths ago, I bought a 120W folding "blanket" charger from JayCar and never bothered with the PWM that came with it. Having done a lot of research via reading and talking to outfitters, I went straight to a Victron MPPT and just have the PWM as an emergency spare. I figured if the el-cheapo folding panel ever fails, or as solar panels become more efficient, I'll always have a quality and very efficient regulator.

Thanks Redtail. I've looked at the Victron and agree with you it's probably the way to go as it has Bluetooth as well. Where do you mount it? The pocket on my panels that houses the existing PWM is too small for the new controller so it would have to "flap in the breeze"

Interestingly, these guys Attention Required! | Cloudflare (https://www.australiandirect.com.au/buy/kickass-dc-dc-mppt-solar-battery-charger-12v-24v-2/KADCDC25A) are promoting their "KickAss" brand (stupid name) and I know it's just a generic Chinese unit re-badged but is affordable and would accommodate an upgrade of battery setup to lithium in the future.

[DiscoMick]

I have a Kickass 120 amp AGM and it has been fine for three years, if that helps.

[Redtail]

Thanks Redtail. I've looked at the Victron and agree with you it's probably the way to go as it has Bluetooth as well. Where do you mount it? The pocket on my panels that houses the existing PWM is too small for the new controller so it would have to "flap in the breeze"

Interestingly, these guys Attention Required! | Cloudflare (https://www.australiandirect.com.au/buy/kickass-dc-dc-mppt-solar-battery-charger-12v-24v-2/KADCDC25A) are promoting their "KickAss" brand (stupid name) and I know it's just a generic Chinese unit re-badged but is affordable and would accommodate an upgrade of battery setup to lithium in the future.

Usually the fold out solar panel lays on the windscreen with the cable running back along the drivers side on the edge of the roofrack and down to the tailgate. The regulator isn't mounted per se, I just sit it where it's convenient, usually on the window shelf above the jack hatch where the Traxide power connector is. Given it's a very fat cable (6G?) back to the battery, I'm not concerned about voltage drop.
Like that, I can lock the car, and the only thing easily nicked would be the panel.

It gives me flexibility to mount the solar panel anywhere else it may be convenient, or charge a third battery box. All connectors are Anderson types, much like LRD414's setup.
(See https://www.aulro.com/afvb/l319-discovery-3-and-4-a/251790-traxide-system-solar-charging.html#post2700895)

The Victron bluetooth is excellent, as are the bluetooth monitors I've put on on each battery. I don't have to get out my chair to check the state of any of it. :-)

[DiscoMick]

Yes, I have done similar with ours, or else chucked it up on the roof rack, plugged in at the rear. I have a portable PWM, but also have mounted versions. I also have a portable ammeter with Anderson plugs I can plug in anywhere I want to know what is happening.