SDHQ vs Slee Dual Battery

[eizenjin91]

I’m hoping someone can give me some info on a dual battery system. I’m comparing two the Slee dual Battery Kit ($655) and the SDHQ complete kit ($1,260). Obviously the SDHQ kit is double the price and comes with precrimped battery cables. It comes with a Blue Sea ACR vs the Slee comes with the RedArc BCDC. I know that RedArc is what all the cool kids are using these days and seems to be taking over the offroad segment in the states from trailers to engine bays to solar. I’ve used Blue Sea ACR before. Never used the RedArc stuff and never used a BCDC (is there a benefit in our 200 series trucks?)
TLDR; is SDHQ worth double the money, which system will charge and maintain the dual battery system better ACR or BCDC, which should I go with who has good or bad experiences with either? Thanks!

 

[mobi-arc]

2x for a mechanical relay package? Nuts.

 

[eizenjin91]

2x for a mechanical relay package? Nuts.

I’m assuming it’s for billet brackets hold down etc but yes to put it simply 2x for a mechanical rather than electric relay. That’s why I was looking for feedback lol. Thanks Mobi-arc

 

[TeCKis300]

The Slee is the only one that's architected right with a BCDC.

SDHQ's ACR based setup is questionable as it won't effectively charge dual batts. Granted, they are providing lots of designed hardware. It is a pretty hefty sum compared to what a homebrewed solution could be.

 

[mobi-arc]

The Slee is the only one that's architected right with a BCDC.

SDHQ's ACR based setup is questionable as it won't effectively charge dual batts. Granted, they are providing lots of designed hardware. It is a pretty hefty sum compared to what a homebrewed solution could be.

Disagree. A limited current dc-to-dc charger is one of many ways and not necessarily the best.

 

[TeCKis300]

Disagree. A limited current dc-to-dc charger is one of many ways and not necessarily the best.

For that price of entry, shouldn't one expect the best?

There's been cases even on this board where using a similar setup, with a deeply discharged aux battery, that there's simply not enough voltage to adequately charge the aux battery. A temperature compensating alternator cannot respond and tender dual batts at various states of charge on a common circuit. Leading to one of the batts systemically undercharged. That leads to microcurrents, or low grade cycling, as the batteries attempt to balance. And sulfation. Factors ultimately leading to premature failure of one or both batts.

There's workarounds.

Some rely on regularly plugging in the car to charge and balance the batteries. I would think having to manually plug in is probably not desirable?

Some have used fuse diodes to make the alternator run hotter, creating excess voltage to facilitate charging, making it work similar to old school non-compensating alternators where ACRs do work. Like old systems, it may also create the need to water batteries, and compromise battery longevity.

A well designed system should keep all the benefits of modern electrical systems, where batts today need no maintenance and last well into 6+ yrs. Unless one lives in an extremely hot climate and all bets are off.

 

[rlynch356]

I have stopped using the relay type dual battery solenoids in both of my trucks.. Why? Voltage drop and basically they do not effectively charge an AGM battery.
if you want cheap I would just use a manual battery combiner switch.

Side note: I have also stopped using AGM for the main battery as well, since our alternators do not put out enough voltage to effecting charge it either.. so it's a waste of money. The system was designed for lead acid batteries.

Otherwise a DC/DC charger will fully charge the battery, just like a plug in to the wall battery charger. It limits current coming out of the charging system into the 2nd battery, (thats wha the 20/40amp ratings are..)
Redarc and Renogy also have a solar input, can do lithium batteries, etc. Victron is also a good known brand, but is all separate modules which can be and advantage.

If none of that stuff is important... just use a battery switch.

 

[Drivn N Cryin]

Having the SLEE installed as I write this. The nice thing about the Redarc is that I can hook up my portable solar panel to it as well for keeping it charged while parked.