test

[gregmchugh]

In many cases it appears that the auxiliary AGM on the ecotrek vans is a single 12 volt battery maybe 80-100 amp hours so if for some reason Roadtrek didn't cover it for 6 years then it is nothing like paying for the 8 AGMs on the eTrek which now have a 1 year warranty...

[Davydd]

Here are your Roadtrek Etrek AGM under hood batteries for the Li-ion Etreks. Two 6 volt batteries?

[cruising7388]

Originally Posted by Davydd

Here are your Roadtrek Etrek AGM under hood batteries for the Li-ion Etreks. Two 6 volt batteries?

I might well be wrong about this but I don't think these are AGMs that support the BMS for lion batteries. I think these batteries are part of an 8 battery Etrek where two of the eight coach batteries are under hood.

Incidentally, I wonder how the AGM maintenance battery is charged? By the primary alternator? By the under hood generator? And when shore power is used, is it charged at all? And if so, how does it deal with the algorithm setup for lion battery charging?

[gregmchugh]

There are several reported configurations of the aux AGM on the ecotrek vans. Some Sprinters are as Davyydd showed with the typical two 6 volt batteries but some have a single 12 volt battery in that location. The Zions seem to have a single 12 volt battery mounted under the rear on ecotrek vans. Not sure where they are on the Chevy vans. As it typical with Roadtrek, there are lots of variations...

It appears that the aux AGM battery (or batteries) are always connected to the charge terminals on the ecotrek modules along with the engine generator. I have not seen any info on what type of battery charge profile is used by the Balmar regulator to handle the fact that there are AGM and lithium batteries connected in parallel for charging.

The inverter/charger is on the load terminal side of the ecotreks and the solar controller seems to vary from one side to the other at least that is what it appears from various reports by owners.

Same thing on the other two chargers, no info on what battery charge profiles they may be using. When the ecotreks are completely online then any charger is charging the AGM in parallel with the lithium cells. Shore power charging from the inverter/charger and solar charging from the solar controller. One question of interest is what happens when the ecotrek battery modules shut down at the maximum discharge point? If the load terminals are disconnected from the battery cells at this point and the charge terminals are still connected does that mean the you cannot recharge from shore power? Similar question on the other extreme, if the battery cells in a module reach maximum charge what happens to prevent further charging? If you are using engine generator charging you must disconnect the charge terminal from the cells. If you are on shore power and disconnect the load terminal to prevent overcharging you would eventually disconnect all the batteries from the inverter/charger. What happens then??

[Davydd]

Originally Posted by cruising7388

I might well be wrong about this but I don't think these are AGMs that support the BMS for lion batteries. I think these batteries are part of an 8 battery Etrek where two of the eight coach batteries are under hood.

Incidentally, I wonder how the AGM maintenance battery is charged? By the primary alternator? By the under hood generator? And when shore power is used, is it charged at all? And if so, how does it deal with the algorithm setup for lion battery charging?

Those are the discussed AGM batteries on a Roadtrek that had 800ah of lithium ion batteries in the back under the floor. I took the photos at the RV Super B Show in Glendale, AZ last spring.

[cruising7388]

Originally Posted by gregmchugh

There are several reported configurations of the aux AGM on the ecotrek vans. Some Sprinters are as Davyydd showed with the typical two 6 volt batteries but some have a single 12 volt battery in that location. The Zions seem to have a single 12 volt battery mounted under the rear on ecotrek vans. Not sure where they are on the Chevy vans. As it typical with Roadtrek, there are lots of variations...

It appears that the aux AGM battery (or batteries) are always connected to the charge terminals on the ecotrek modules along with the engine generator. I have not seen any info on what type of battery charge profile is used by the Balmar regulator to handle the fact that there are AGM and lithium batteries connected in parallel for charging.

The inverter/charger is on the load terminal side of the ecotreks and the solar controller seems to vary from one side to the other at least that is what it appears from various reports by owners.

Same thing on the other two chargers, no info on what battery charge profiles they may be using. When the ecotreks are completely online then any charger is charging the AGM in parallel with the lithium cells. Shore power charging from the inverter/charger and solar charging from the solar controller. One question of interest is what happens when the ecotrek battery modules shut down at the maximum discharge point? If the load terminals are disconnected from the battery cells at this point and the charge terminals are still connected does that mean the you cannot recharge from shore power? Similar question on the other extreme, if the battery cells in a module reach maximum charge what happens to prevent further charging? If you are using engine generator charging you must disconnect the charge terminal from the cells. If you are on shore power and disconnect the load terminal to prevent overcharging you would eventually disconnect all the batteries from the inverter/charger. What happens then??

The undeniable sign of an excellent post is one that asks more questions than it answers.

What I don't understand is, why would you need an AGM(s) with this amp hour capacity to accomplish what we are told it's presumably supplied for, to wit:

a. If the lion battery shuts off, provide a load to permit operation of the UH generator or the shore power function.

b. Provide a momentary power source to initialize a BMS in a shut down condition.

[booster]

Originally Posted by cruising7388

The undeniable sign of an excellent post is one that asks more questions than it answers.

What I don't understand is, why would you need an AGM(s) with this amp hour capacity to accomplish what we are told it's presumably supplied for, to wit:

a. If the lion battery shuts off, provide a load to permit operation of the UH generator or the shore power function.

b. Provide a momentary power source to initialize a BMS in a shut down condition.

You need a 12v source with capacity, eg battery, to get the charging sources to initialize and also to run. There are a bunch of tests the smart chargers do to prove they have a real battery in the circuit both to start and to stabilize and run. I tested this a bunch when I was working with our Blue Sea charger.

[cruising7388]

Originally Posted by booster

You need a 12v source with capacity, eg battery, to get the charging sources to initialize and also to run. There are a bunch of tests the smart chargers do to prove they have a real battery in the circuit both to start and to stabilize and run. I tested this a bunch when I was working with our Blue Sea charger.

OK......but 200 ah capacity?

[gregmchugh]

As I mentioned they seem to be using a single 12 v 80-100 amp hour AGM in many cases, even on the Sprinters, but Roadtrek is very consistent in their inconsistency, hard to find two vans wired the same sometimes...

[booster]

Originally Posted by cruising7388

OK......but 200 ah capacity?

200ah capacity is useless if it is in low voltage or too cold cutoff. Then it has exactly zero amp hours and zero voltage.