Lithium and AGM combo system like Hymer - Page 4

hbn7hj · 03-01-2018, 04:01 AM

Ordered. Thanks to George for finding it. I'm planning on using 6 gauge wire, short leads, to put it all together.

hbn7hj · 03-01-2018, 07:37 AM

What happens if a depleted lead acid is shorted to a full lithium? It appears the B to B charger needs to be in series with the lithium at all times. Booster, if you test this wear eye protection!

I've got a couple of 50 amp resettable DC breakers. One on the ground lead of the lithium battery?

booster · 03-01-2018, 08:00 AM

Quote:

Originally Posted by hbn7hj

What happens if a depleted lead acid is shorted to a full lithium? It appears the B to B charger needs to be in series with the lithium at all times. Booster, if you test this wear eye protection!

I've got a couple of 50 amp resettable DC breakers. One on the ground lead of the lithium battery?

That is exactly why you need a current limiting B to B charger. If you didn't have the current limiting the acceptance of the AGM would be too high and draw too much current. It would be too much for the AGM to handle for long without overheating.

The AGM and lithium will be wired in parallel through the battery selector switch or if the B to B charger is turned on though the switch.

If you did accidentally connect an empty AGM to the full lithium by putting the switch to "both" setting, you would cause the too high a current thing. I think I would put breakers or fuses in each of the battery lines btween the battery and the switch at about 20 amps higher than your shore charger capacity is. That would make the system safe against the switch position error.

hbn7hj · 03-02-2018, 01:08 AM

All lithium battery output will go through the B to B charger. The lithium battery will have it's own AC powered lithium charger. The both position will be used to charge the lead acid battery from the lithium and run the coach. The only thing I cannot do that I might want to do is to solar charge the lithium battery. The solar connection to the lead acid battery is made at the power panel on the other side of the coach so I'll skip that for now.

50 amp fuse on the ground lead of the lithium battery. 50 amp fuse on the power lead of the lead acid battery already present.

booster · 03-02-2018, 02:11 AM

Interesting way of doing it. Two separate chargers gives you a lot more options than using one and charging both batteries of it at the same time. I think a multibank charger would also work, but not have the versatility of two standalones for profiles.

It is probably good that you have a while before the final install, as it will give you a chance to go through the Kisae manual about a dozen times. Lots of subtle stuff in there to try to tie together. I been through it a couple times and find different stuff each time. It does look like you will need to do a manual override of the low voltage start parameters for the lithium side, as it will be at 13.2v unless you override and then I think it went to mid 12s or a bit lower. It wasn't clear to me yet if those settings are tied to a low volt cutout while charging or not. Hopefully, that would be a little lower, but the BMS may kick in first anyway.

Did you order the remote with it, so it would be a bit easier to see what is going on?

hbn7hj · 03-02-2018, 02:54 AM

Couldn't find the remote to order it. I did find the charger remote but it is a different model number, I'm expecting two battery monitors to give me all important information but if anyone can find the remote for sale I'd be interested in case I need it.

hbn7hj · 03-03-2018, 07:32 AM

Figured out how to get solar to the lithium.

Thinking further ahead (I can see adding more lithium batteries since I have the room) how do you run the whole coach off an inverter? Not interested in running the microwave or A/C which would mean about 1000 watts or less. I guess I need to get back to HandyBob!

VER_1 · 03-03-2018, 08:35 AM

Voltronics VBCS 60/40/430 Triple Battery Charger

This unit does boost the alternator to a higher voltage from my research but is not cheap and the mppt function is limited but also also has a 120v charger. Made in Germany

booster · 03-03-2018, 12:47 PM

Quote:

Originally Posted by hbn7hj

Figured out how to get solar to the lithium.

With the 100ah of lithium you will have, you also would have enough lithium capacity to add another AGM instead of more lithium if you can handle the weight, and save some money.

Thinking further ahead (I can see adding more lithium batteries since I have the room) how do you run the whole coach off an inverter? Not interested in running the microwave or A/C which would mean about 1000 watts or less. I guess I need to get back to HandyBob!

A lot of it depends on how it is currently wired. If you don't already have some outlets wired to the inverter it is usually easier to to get whole van on the inverter.

Normally, you would just break into the AC power line after the shore power/generator transfer switch and put the inverter and another transfer switch there to switch between shore/generator and inverter AC power.

If you have any outlets that already on the inverter, they probably are run from an internal transfer switch in whatever inverter you had before and would need to be moved to be on the main power to the van and not separate.

I did our van this way using the internal transfer switch that is in the Magnum inverter. I was able to use the original wiring from the fuse box to the original small charger to move the old inverter outlets to the main wiring circuit. Full 30 amps of input AC now go directly to the Magnum, as the transfer switch is full size 30 amp. I took out the original transfer switch because we no longer have a generator.

BBQ · 03-03-2018, 03:08 PM

.

Any small inverter (150w or less?) can go through a cig lighter socket.

Anything bigger than that should be hardwired. (You will need heavier gauge wire.)

hbn7hj · 03-03-2018, 03:28 PM

No presently installed inverter. I'm contemplating the change in wire gauge. The problem is I'm in Borrego Springs and all my parts are in Phoenix! Since I can't work on it I keep screwing with the plan. Need to quit that!

Interesting comments about Battle Born BMS (was it erased) about charger glitches shutting them down. Don't know how good my charger is. PD 60 lithium charger.

booster · 03-03-2018, 05:15 PM

Were the Battleborn comments on this thread? I don't remember seeing them.

hbn7hj · 03-03-2018, 06:01 PM

REV must have erased them but not before they were sent out to thread participants.

"I have been researching Battle born but they have a very bossy BMS as I just imagine being out in the boonies when it shuts down altogether if it thinks it sees a glitch by not having a proper charging system. I could be wrong but you gotta control all aspects of charging to these batteries with an internal BMS with external cutoffs for high and low voltages. As some chargers seem to overshoot the voltage and shut these batteries internal BMS system down. Then no power out in the woods. So if it is not properly put together then maybe you should keep a few agm batteries with yeah as I have seen customers almost cry telling me their horror stories when their vacations should of been a highlight in their lives but became a nightmare."

VER_1 · 03-04-2018, 01:32 AM

I did remove as I was up late and saw my spelling and english grammer so I decided to post later.

I am new here too so I don't want to say too much until you guys get used to me. Thanks

VER_1 · 03-04-2018, 01:40 AM

The owner of light harvest solar in portland also supported the claim about the bossy Battle Born Battery BMS system. Or for that matter possible all BMS systems hypothetically. As he is comparing alot of lithium batteries I think to find the biggest bang for the buck. But I would advise that someone not take this approach without a complete BMS system in the battery and outside the batter.

Heres the link

https://www.youtube.com/watch?v=U6l82LlCjhU

I hope the forum is ok with me linking.

VER_1 · 03-04-2018, 02:06 AM

Here is another video of a Lithium Battery with a internal BMS installed. I followed the saga and got a good laugh of the installation and the difficulty of connecting the battery up. I guess we all learned similar to this guy but at 16 years old I was already inclined but for the newer generations they are just used to turn the key and start the car these days.

Towards the end you will see the lithium battery work when it wants to. I suspect without voltage controls externally this will be common with smart batteries that are tightly managed by its internal profiles. So a Battery to battery converter is required in some instances or external high and low cutoffs required to help prevent triggering the internal BMS from shutting down.

The poster removed the comment on youtube as poor guy as I am sure he got alot of feedback. Thanks

https://www.youtube.com/watch?v=TES9_eYoJ84

eric1514 · 03-04-2018, 01:01 PM

Herewin Battery

Very Tempting.

hbn7hj · 03-04-2018, 03:47 PM

Quote:

Originally Posted by eric1514

Herewin Battery

Very Tempting.

$41 compared to $1000 would tempt anyone.

booster · 03-04-2018, 05:42 PM

Quote:

Originally Posted by hbn7hj

$41 compared to $1000 would tempt anyone.

We wish

in small quantities $419.

VER_1 · 03-04-2018, 09:39 PM

The potential problem with these batteries are the same problems light harvest solar in Portland had with cheaper solar charge controllers he sold. As he is thrifty and most people are so finding that option that can work at the lowest price is appealing to alot of buyers.

He now offers another solar charge controller a chinese brand which seems to be most exclusive to him. As can't find other sellers unless mail order from china. On top of this the other cheap chinese controllers he sold in the past he now points out the problems on the website they have had. But for some reason these new ones are the King stuff.

Leaves very little credibility in my view as sometimes spending more on a proven product is a wise choose. However on the other end of the spectrum maybe he has learned the hard way and is doing more tests before offering to his customers. I support him as I appreciate the results he shares and now the honesty too.

Light Harvest Quote

"Since we test so many products, we have come to find that about 1 in 4 "mail order" charge controllers work as advertised, about 1 in 10 we like, and only the rare few we will sell. At first, we sold the black ones with gold faces, but they got hot and the screen went dark. Then we sold the Tracer series with no meters, good but expensive and feature shy. Then we sold the EP series but those had 1 serious flaw and could not develop full power in low light. We've tried a big list of other controllers too, they range from OK to D.O.A .

Of course, price, and functionality absolutely have to be top notch and the SRNE's have excelled where others fell short. Right out of the box the quality is apparent.

Remote meter available for the data hungry or when you have to tuck the controller out of sight.

All controllers have a down side, and the SRNE has pesky terminals, so be patient there.

The SRNE MPPT's also comes with remote battery temperature sensor."

SRNE ML4860, 60 Amp MPPT Digital Solar Charge Controller

You may also like: