Mercedes-Benz Metris Forum banner
1 - 13 of 13 Posts

·
Registered
Joined
·
81 Posts
Discussion Starter · #1 ·
I pretty much completed my cargo van conversion a while back but never completed a secondary battery installation beyond installing the wiring behind, and within, the cabinetry. I had planned the easy route by going with an Inergy Kodiak unit but decided to wait until their new product, the Apex was available. The Apex is currently available for $1579. Expensive but it seems to do everything I needed but I was not sure about charging it from the vehicle through the lighter socket as suggested. Almost ordered one but…

The route I eventually took was decided yesterday when I found an eBay posting for Valance 12V 138 Amp hr Lithium Phosphate batteries for $399 plus $30 shipping. These are used units with, according to the seller, less than 300 cycles and tested for charge and discharge. (units are supposed to be good for 5000 cycles or more) Research on the web came back with multiple users having good experience with used Valance Batteries on various projects. I decided to get one shortly after the posting was listed and there were 6 sold by the time I completed my purchase. Now, a few hours later 15 are sold with 92 watchers so it seems people are finding these batteries desirable. Unfortunately the seller has now updated his posting by increasing the price to $449 each. The eBay URL is ridiculously long so will not post it. If interested this is the posting title on eBay.
12V 138Ah Valence Lithium Phosphate Battery (Great for RVs)

So now I have to do the research and design an installation. I am hoping to follow RansomRidge’s lead and install a battery to battery charger from Sterling. I am not sure RR’s charging unit will work with a Lithium battery so Ill have to educate myself on these units as well as solar charger options.

Constructive advise welcomed. In other words, I do not need to be reminded about the foolishness of buying a $400 used battery on eBay
 

·
Registered
Joined
·
81 Posts
As advertised, the battery looks like a great value! I took my chance buying lithium cells from ebay as well so your purchase is well within my risk parameters. :cool:

I came across this charger when I researched my setup:


I didn't using it because I ended up with a 24v system. From what I read, the charger has good reviews. The one drawback is that although it can be connected to both solar and starter battery, it can't take charge from both sources simultaneously.
 

·
Registered
Joined
·
81 Posts
Discussion Starter · #3 ·
As advertised, the battery looks like a great value! I took my chance buying lithium cells from ebay as well so your purchase is well within my risk parameters. :cool:

I came across this charger when I researched my setup:


I didn't using it because I ended up with a 24v system. From what I read, the charger has good reviews. The one drawback is that although it can be connected to both solar and starter battery, it can't take charge from both sources simultaneously.
Thanks for the information. I will take a closer look at the Abso unit. Was also looking at the Redarc BCDC1225D charger from Australia sold through etrailer. https://www.etrailer.com/Battery-Chargers/Redarc/331-BCDC1225D.html
The positive - these units have built in MPPT solar regulators along with the DC to DC charger and they do have a Lithium charging profile listed. The positive for the Sterling charger is that several on this forum have installed them so I know they work with the Metris system. I haven't made my mind up yet.
As far as the 138Ah Valence Lithium battery I bought on eBay on Thursday, it is scheduled to be delivered Monday. I see there are now 74 units sold on the eBay listing so the seller upping the price $50 didn't slow the demand.
 

·
Registered
2016 Cargo converted into a camper van
Joined
·
341 Posts
The Redarc BCDC1225D looks like a good setup. It delivers more continuous power than the Sterling and has the MPPT controller for solar. One extra challenge with the install would be connecting to the ignition wire for low voltage charging (ie below 12.7 volts for the "smart" alternator on the Metris.)
 

·
Registered
Joined
·
81 Posts
Discussion Starter · #5 ·
The Redarc BCDC1225D looks like a good setup. It delivers more continuous power than the Sterling and has the MPPT controller for solar. One extra challenge with the install would be connecting to the ignition wire for low voltage charging (ie below 12.7 volts for the "smart" alternator on the Metris.)
I was planning to connect the hot lead to the A2 catch like you did in your installation. At position A2, it is my understanding the charging unit would then work only when the ignition was on. Would a different hot connection be required for units like the Redarc chargers?

This is the area I need to learn more about. Is it because of regenerative braking, or something similar, will not allow the alternator to fully charge the starter battery to full capacity? And the results being the smart alternator would not providing adequate charging voltage for a secondary battery? Sterling says their units compensate for this while others I am not sure.
 

·
Registered
Joined
·
81 Posts
The description of the Redarc unit says it has "built in battery isolator function".

In my own setup, I pulled the power through terminal 30 of the EK1 box (near the right foot of the front passenger). It's rate 25A max so may fit well with the Redarc unit you are looking at. Since EK1 is the "official" power outlet from the van, I had assumed it will have more stable voltage profile than tapping the starter battery directly, but I honestly do not know. It did work well with a small boost charger I have.
 

·
Registered
2016 Cargo converted into a camper van
Joined
·
341 Posts
I'm not sure how the Sterling accounts for the voltage drop with the "smart" alternators. Presumably through internal circuitry. I see no reason why the A2 catch wouldn't work as the power source. It certainly works good in my van (a 2016 cargo model). I can't see the display showing the voltage going into my aux battery while I'm driving so I don't know how constant (steady) the voltage being supplied is while I'm driving.

My comment on connecting to the ignition wire is based on the Redarc installation diagram on their website for a vehicle with a smart alternator. Apparently that is how this unit knows the vehicle's ignition is turned on whereas the Sterling has internal circuitry for that function.

QNF- I do not have the EK1 option on my van which is why I used the A2 catch. If I had the EK1 option I'd have used that first since that's what its made for.

Redarc has an explanation on the old style alternator vs the smart alternator. https://www.redarc.com.au/alternator-vs-fixed-alternator.
 

·
Registered
Joined
·
81 Posts
Discussion Starter · #8 ·
I'm not sure how the Sterling accounts for the voltage drop with the "smart" alternators. Presumably through internal circuitry. I see no reason why the A2 catch wouldn't work as the power source. It certainly works good in my van (a 2016 cargo model). I can't see the display showing the voltage going into my aux battery while I'm driving so I don't know how constant (steady) the voltage being supplied is while I'm driving.

My comment on connecting to the ignition wire is based on the Redarc installation diagram on their website for a vehicle with a smart alternator. Apparently that is how this unit knows the vehicle's ignition is turned on whereas the Sterling has internal circuitry for that function.

QNF- I do not have the EK1 option on my van which is why I used the A2 catch. If I had the EK1 option I'd have used that first since that's what its made for.

Redarc has an explanation on the old style alternator vs the smart alternator. https://www.redarc.com.au/alternator-vs-fixed-alternator.
Thanks QFN & RR for your input. I also have a 2016 Metris without the EKI option so RR"S solution using the 100 amp A2 catch seems like a good choice. It seems to me the 150amp A12 catch (aux battery) catch would work also but haven't gotten far enough into this to see if there may be hidden issues with that source. Liking the Redarc BCDC unit the more I learn about it. They claim their unit will charge lithium and work with the variable output alternator on the Mercedes Vito. It also appears to do what I need for solar.

My eBay Valence 138 Ah lithium phosphate Battery arrived in good order and charge on Monday. The eBay seller sold out his 135 battery inventory pretty quick. May regret not getting two at $399 when I had the opportunity but one battery should meet my requirements for now.
 

·
Registered
Joined
·
85 Posts
IIRC, that battery is designed to be used with an external controller. Usually there is a bus connector that plugs into the controller. If it is the one that I am thinking of, it requires external relays / contactors for safety.

Is that what you have?
 

·
Registered
Joined
·
81 Posts
Discussion Starter · #10 ·
IIRC, that battery is designed to be used with an external controller. Usually there is a bus connector that plugs into the controller. If it is the one that I am thinking of, it requires external relays / contactors for safety.

Is that what you have?
Not Really. The battery I purchased through eBay was manufactured by Valence and has an internal Battery Management System. What I understand is the built in BMS protects from overcharge and over discharge, as well as temperature protection. The cables on the battery allow multiples to be tied together for load balancing etc. But I only have one battery. People have hacked together a simple cable from these batteries to their PC to access a full report on the units function using Valence software. I've discovered one reason for large quantities of these batteries being available, from time to time, is because critical use industries, like hospitals, require the units to be changed out periodically, regardless of use.
Of course I can't verify the function of the batteries BMS because it's LED is blinking away (a good thing) on my workbench while I wait for all the necessary parts to arrive so I can finish putting the system together. Unfortunately the price is going up. The same source is now selling the 138 aH units on eBay for $100 more than I paid 3 weeks ago. The following link somewhat describes Valence batteries even though the discussion is about a smaller version of the battery.
 

·
Registered
Joined
·
85 Posts
Valance makes a type called the RT version for use in hospital carts and similar, which is a lower capacity version like the guy on youtube has.

I could be wrong, but I am pretty sure that the 138s are not the RT type. They have a balancing board inside and communications, but they don't have built in shut down hardware (relays for example ) internally like for instance battle born.

I am not an expert, but I am a commercial user of these and have designed battery packs using these batteries and control systems. It is a non trivial experience to design a system using these batteries. They assign an applications engineer to you and a manual over 100 pages long with instructions and suggestions. Frankly, if you don't follow their suggestions, they won't do business with you, because they are super safety oriented.

They are a fantastic battery, but AFAIK, the electronics inside are mostly for sensing, not control. You are using them essentially "unprotected" from all Li oriented protections. Sensing / measuring is not the same as control.

Unfortunately the acronym BMS can mean both:
  • Battery Monitoring system
  • Battery Management system

Monitoring is the equivalent of a bunch of electronics that will watch you drive your car into a wall at 60 mph and record the event.

Management implies that it will use this information to auto turn on the brakes and keep you from crashing.

AFAIK, the 138s have a "monitoring" system.
 

·
Registered
Joined
·
81 Posts
Discussion Starter · #12 ·
Valance makes a type called the RT version for use in hospital carts and similar, which is a lower capacity version like the guy on youtube has.

I could be wrong, but I am pretty sure that the 138s are not the RT type. They have a balancing board inside and communications, but they don't have built in shut down hardware (relays for example ) internally like for instance battle born.

I am not an expert, but I am a commercial user of these and have designed battery packs using these batteries and control systems. It is a non trivial experience to design a system using these batteries. They assign an applications engineer to you and a manual over 100 pages long with instructions and suggestions. Frankly, if you don't follow their suggestions, they won't do business with you, because they are super safety oriented.

They are a fantastic battery, but AFAIK, the electronics inside are mostly for sensing, not control. You are using them essentially "unprotected" from all Li oriented protections. Sensing / measuring is not the same as control.

Unfortunately the acronym BMS can mean both:
  • Battery Monitoring system
  • Battery Management system
Monitoring is the equivalent of a bunch of electronics that will watch you drive your car into a wall at 60 mph and record the event.

Management implies that it will use this information to auto turn on the brakes and keep you from crashing.

AFAIK, the 138s have a "monitoring" system.
Thanks for this information-very helpful. Being unable to find details on how this battery functioned as far as protection for my intended installation I had decided to incorporated external battery management in my design. Thinking if the battery did provide a function of protection it would be secondary to installing external components I would have confidence in. I was wondering why some YouTubers were opening the battery cases and replacing the BMS circuit board in order to meet their installation requirements. Now I somewhat understand why.
 

·
Registered
Joined
·
85 Posts
It is not completely trivial, but possible to purchase and integrate the official standard valance controller into the pack that you have.

Before you make this decision, keep in mind that these batteries are rated for battery banks up to around 6-700 volts , so the company's designs are conceived around this level of performance. Battle born makes some very nice batteries, but by comparison, a BB is ~ 80 amp x 48 volt system, vs these are ~ 600 volts x 150 amps. It is quite a difference in design requirements. It is sufficient for most van applications, but we are sort of an electric upgrade speed shop, so you know how it is.

We use them as 48 volt DC systems, so quite conservative by comparison. Nonetheless, we end up using the contactors that Valence chose for this level of operation, which are frankly some pretty dang impressive TEC contactors which run ~ $180 / each last time I checked. Yes you can really run an EV on these things and they are designed for ocean rated service.

My original plan was to operate at 270 VDC, but after a lot of work, I decided that it was too dangerous for most customers, so we dropped down to 48 and 24 volt systems.

The last time I purchased controllers they were ~ $400 ish.

The biggest PITA was actually crimping related for the connectors.

In their defense, those valence batteries are really impressive in terms of what they can do.

Take a look at the number on your battery. Typically they are part of a "string" and the batteries are numbered in a sort of 1 to xxx. Sometimes the battery has to start with number "1" in order for the controller to recognize it.
 
1 - 13 of 13 Posts
Top