My motorhome has 400W of solar in two strings of two panels each, feeding two 6 volt, 210 AH Costco golf cart batteries. I’d like double the usable capacity to 200 AH with a single 12 volt, 200 AH LiFe battery. I do have the space for four golf cart batteries, but I don’t trust the battery slide tray to carry 240 lbs of batteries (60 lbs for the LiFe battery). The conversion requires a LiFe battery ($1000) and two MPPT controllers ($100 ea, one for each string). The inverter/charger has a LiFe setting, so no changes needed there.
My main question is about the LiFe battery that looks like a good choice: the Renogy 12V LiFe unit with Bluetooth monitoring, 200 amp max continuous discharge, a BMS with all the usual protection including low-temperature charging disconnect - $1000 with shipping. The specifications:
12V 200Ah Lithium Iron Phosphate Battery w/ Bluetooth (https://www.renogy.com/12v-200ah-lithium-iron-phosphate-battery-w-bluetooth/)
I’m assuming the Onan 4kw generator won’t have any problem starting from this battery, as it can supply 240 amps for 15 seconds without tripping the over-current protection.
1) Does anyone know of a better choice than the Renogy?
I haven’t chosen the two MPPT controllers, each of which will be used with two 100W, 7 amp max output solar panels in series. The outputs will be in parallel on the battery. It’d be nice if they had remote indicators that could be mounted near the inverter/charger control panel, but built-in displays would work.
2) Any suggestions for the MPPTs?
I believe the LiFe battery is safe if the alternator is directly connected to the battery, though it probably doesn’t get fully charged that way. My concern is the alternator may harm itself trying to charge a large LiFe battery, but I haven’t found any definitive information on charging a LiFe battery directly from a standard (2004) E450 alternator. I’ll skip alternator charging for now by disconnecting the OEM charge cable in the engine compartment. But still ...
3) Does anyone know if the E450 alternator can handle charging a LiFe battery directly?
Eric,
Lithium coach batteries need an interface between the truck chassis alternator and the lithium batteries. This adjusts the charging voltage from alternator to the lithium batteries.
When having all my solar/lithium batteries installed at AM Solar, they placed a Victron Cyrix-Li-Ct relay between the alternator and the solar/lithium charging system. Everything works perfectly. Not sure if this will be appropriate for your LD model year.
The Cyrix-Li-Ct relay can be purchased directly from AM Solar or possibly from Victron.
Hope this helps.
Kent
$999 is a very low price for a 200 Ah LiFePO4 battery. A pair of Battle Born 100 Ah lithium batteries--a popular low-end choice--will run you $1,600 and up, last time I checked. A single 200 Ah Victron "Smart" lithium battery costs about $2,000. Two 100 Ah batteries from Lithionics, a high-end manufacturer, cost upwards of $3,000. Given the extremely low price, I have to wonder where Renogy is cutting corners. Another concern: they have a reputation for poor customer service. If anything goes wrong...
I'll give Renogy credit for including Bluetooth in a battery this cheap. That means you can get a look at what's going on inside the battery, and (I assume) upgrade its internal software if necessary, using a smartphone app.
For what it's worth, the screenshots below show the kind of information you can get from Victron's and Lithionics's iOS apps. Renogy's app requires signing up for an account, so I haven't been able to see what information it provides. Battle Born, lacking Bluetooth, doesn't let you access this kind of information. I wonder how long before competition forces them to add that ability?
3) Does anyone know if the E450 alternator can handle charging a LiFe battery directly?
No the E450 alternator can not handle charging the LiFe battery directly. Li batteries have very low resistance and will allow an excess of current from the alternator to flow to the Li battery which will result in your alternator overheating.
In order to move away from the lead acid battery to a LiFe battery you will need to replace the Lazy Daze factory battery isolator circuit with a DC to DC charger. The DC to DC charger will regulate the amount of current flowing from the alternator to the Li battery to prevent your alternator from overheating.
You will want to chose the current capacity of the DC to DC charger so that it does not exceed the available excess charge capacity of your alternator.
Several of us have gone lithium. There are four problems to solve.
1. Freezing temperatures.
2. Solar charging.
3. Converter charging.
4. Alternator charging.
Everyone I know has the lithium batteries inside the heated space. Batteries with heaters are now available.
Solar chargers with a lithium profile are now available.
Converters with a lithium profile are now available.
We all solved the alternator charging in different ways.
You have two and three solved. One and four to go. Have fun, you will enjoy lithium.
Several of us have gone lithium. There are four problems to solve.
...
4. Alternator charging.
...
We all solved the alternator charging in different ways.
One way is to simply disconnect the charge line to the house battery, and do without alternator charging; I'm aware of the DC DC charger method, and that would be easy to do; I've heard of alternators with current limiting ability, but that appears more expensive and difficult than the DC DC charger. What are the other methods normally used?
One way is to simply disconnect the charge line to the house battery, and do without alternator charging; I'm aware of the DC DC charger method, and that would be easy to do; I've heard of alternators with current limiting ability, but that appears more expensive and difficult than the DC DC charger. What are the other methods normally used?
I retained the original batteries and left the original isolator and batteries untouched. Lithium charging is done only by solar and generator. I can use the lithium batteries to charge the flooded lead acid batteries with a DC to DC charger.
It is not a simple system. It has been working very well since 2017.
Lithium charging from the generator peaks at 120 amps so doesn’t take long. 14.3 volts is full.
2003 Roadtrek hybrid battery system - Class B Forums (https://www.classbforum.com/forums/f23/2003-roadtrek-hybrid-battery-system-8526.html)
Hi Eric; I'm in the process of converting to LiF batteries. I chose S.O.K. batteries but I haven't actually hooked them up yet. (any week now) Two at $1029 each. Rated at 206 AH. That gives 412 AH total. I have crammed both into my present battery box, including a (intended for water holding tanks) 12 VDC sheet heater.
#1; The heater has an internal thermostat. It has been tested sort of. It was cold enough in San Diego to have it come on at 40 degrees, but just for a few seconds. It is between the batteries and the outside compartment door. Soon to be insulated, and (I hope) air and water tight.
#2; Solar I replaced my old solar panels. Now 350 Watts. The R3000i can be programmed manually to supply a higher voltage. 14.2, 14.4 or 14.6 volts. I picked 14.4, but I haven't tested that yet.
#3; I replaced my converter last year with a Progressive Dynamics.PD4655 Li. LiF compatible. Swapping a jumper changes it to the higher voltage, profile to match LiF.
#4; I got a Renogy 60 Amp Dc to DC converter. It has jumper switches to select LiF voltages and charging profile. There is a D+ 12v signal to enable charging from whatever voltage the alternator puts out, to (up to) 60Amps at 14.6 V to charge the LiFs. A 12V signal applied to the LC input cuts that in half to 30A. (LC=low current) I'm sure my older '99 E350 chassis can handle that, and I will have switches at the dash to control the Renogy box. No charge at start up. 1/2 charge at first, then full charge at 60A if the batteries need it. My alternator is rated for 130 A. With all external lights (not headlights) converted to LED current drain is minimal to run the fuel pump, ignition, instruments. The A/C clutch (with interior air handler fan) , and headlights are certainly a concern. Can't remember if I have an auxiliary electric fan for cooling. The chassis battery can handle that short term. Renogy makes a 20A/10 (LC) and 40A/20(LC) version.
My power demands hopefully won't go up too much, so the increased solar when available should do most of the charging I need. Sometimes the sun doesn't shine. I don't plan to be in cold weather very often. The SOK batteries got good reviews. (The Marine version is too big, and more $$). It does have an internal low temp shut off, but no Blutooth. Steel battery cases. 12V 206Ah LiFePO4 Lithium Iron Phosphate Battery Pack | SOK Battery USA (https://www.us.sokbattery.com/product-page/12v-206ah-lifepo4-lithium-iron-phosphate-battery-pack?gclid=Cj0KCQiA6NOPBhCPARIsAHAy2zDZ_76-P6Z5Ca4jQuvYEMSzyHTJ-n3xzJM0kZDThGcSliCNMgJdVu8aAiP5EALw_wcB).
The Renogy DC/DC-30 can both handle Solar 15A with MPPT and 15A from the alternator. Amazon.com: Renogy 12V 30A DC On-Board Input MPPT Battery Charger for Gel,... (https://www.amazon.com/Renogy-Charger-MPPT-Batteries-Multi-Stage/dp/B093BB3PCV/?_encoding=UTF8&pd_rd_w=7yHSI&pf_rd_p=e3507245-c2c1-4f99-8b1e-89193a9e9975&pf_rd_r=WF1MCY5M5NCCC0WDB43F&pd_rd_r=6aa8b96b-cf2f-4e98-953a-1acb03f130f1&pd_rd_wg=iQAad&ref_=pd_gw_bmx_gp_q95d6rro&th=1) so two of those might do the job for the solar you have set up now. "The Renogy Dual Input DC-DC On-Board Battery Charger with MPPT is designed to charge your service battery to 100% from two inputs: solar and alternator."
Another month and I should have it all working. The 'TK has very little expansion space, which complicates even simple things. I'm still adding a 2KW TSW inverter and more. RonB
How have people solved the heat dissipation challenge of the DC-DC converter from the engine alternator to the lithium batteries? It needs to be mounted on metal, not plastic or wood, due to how hot it can get. That means it needs to live underneath on the truck frame or engine compartment wall, not in the battery box or on the internal wood frame.
I use a Morningstar Sunsaver MPPT, which will control 2 100W panels aimed full sun, or does fine with my 300w flat on the roof. It only has a couple LEDs for readouts, but can hook to optional full panel display. A pair of these with their readouts should work for you. They are extremely rugged and fully programmable with a computer and software. Mine is currently hooked to a pair of Battleborn 100AH batteries.
Steve
p.s. the Renogy 100AH battery uses soft-pack cell technology - may be fine, but uncommon. Will Prowse has a youtube teardown of it. Not sure if the 200AH would use the same technology...
$999 is a very low price for a 200 Ah LiFePO4 battery..... Another concern: they have a reputation for poor customer service. If anything goes wrong...
$1000 for a 12V 200AH LiFe battery isn't cheap anymore. There a numerous brands offering them for less than $700 now, and that might be why Renogy has gone from $1299 to $999 (at least during the sale). I am disappointed to hear their customer service is poor, but at least they are an established brand, unlike the slew of brands in the <$700 range.
How have people solved the heat dissipation challenge of the DC-DC converter from the engine alternator to the lithium batteries? It needs to be mounted on metal, not plastic or wood, due to how hot it can get. That means it needs to live underneath on the truck frame or engine compartment wall, not in the battery box or on the internal wood frame.
I use both the Kisae DMT 1250 and DMT 1230. They have internal fans and work well. Note they also have solar controllers.
The Renogy DC/DC-30 can both handle Solar 15A with MPPT and 15A from the alternator. Amazon.com: Renogy 12V 30A DC On-Board Input MPPT Battery Charger for Gel,... (https://www.amazon.com/Renogy-Charger-MPPT-Batteries-Multi-Stage/dp/B093BB3PCV/?_encoding=UTF8&pd_rd_w=7yHSI&pf_rd_p=e3507245-c2c1-4f99-8b1e-89193a9e9975&pf_rd_r=WF1MCY5M5NCCC0WDB43F&pd_rd_r=6aa8b96b-cf2f-4e98-953a-1acb03f130f1&pd_rd_wg=iQAad&ref_=pd_gw_bmx_gp_q95d6rro&th=1) so two of those might do the job for the solar you have set up now. "The Renogy Dual Input DC-DC On-Board Battery Charger with MPPT is designed to charge your service battery to 100% from two inputs: solar and alternator."
It's very intriguing, but there are quirks, especially the low solar cut-off voltage, according to this user:
https://www.amazon.com/gp/customer-reviews/R2E5IU7P078XDP/ref=cm_cr_dp_d_rvw_ttl?ie=UTF8&ASIN=B093BB3PCV
There is a YouTube by "I'm not lost, I'm RV'ing" with a review of the SOK 206. They have a gray 27 LD. https://www.youtube.com/watch?v=Oez7zrxBwAc
As mentioned by Steve, Will Prowse has a video about the SOK 206 here: https://www.youtube.com/watch?v=GRTmvjcLXxs
For Keith, the 60A Renogy DC/DC voltage booster is at worst 90% efficient. Running at it's maximum rate of 750 W, that is dissipating 75 watts. It has two internal fans and will shut down if it gets too hot. 75 watts isn't all that bad. I don't plan on running it at full power often, more in the 30 A range using the low current mode. (LC) That would dissipate more on the order of 40 W. Like a 40 watt light bulb. I have a temperature monitor near it to watch what is going on. It is mounted on aluminum rails. (More on that later.)
Many videos have the Renogy box mounted in areas that wouldn't be good for excessive heat problems. Compartment bays similar to our storage areas with the felt liner walls, etc. RonB
I believe the LiFe battery is safe if the alternator is directly connected to the battery, though it probably doesn’t get fully charged that way. My concern is the alternator may harm itself trying to charge a large LiFe battery, but I haven’t found any definitive information on charging a LiFe battery directly from a standard (2004) E450 alternator. I’ll skip alternator charging for now by disconnecting the OEM charge cable in the engine compartment. But still ...
3) Does anyone know if the E450 alternator can handle charging a LiFe battery directly?
Battleborn claims their batteries can be connected to the alternator without harm.
If retaining the original isolator wiring and isolator (or relay), I doubt if the 10-gauge wiring can pass enough amperage to damage the alternator. This could make the DC to DC converter an unnecessary expense.
Ford has increased the alternator output through the years, 130-amp to 225-amps, depending on the model year.
Watching our LD's battery monitor, I have never seen our 2003's 130-amp alternator charge the coach battery at over 45-amps, where the PD9270 converter will charge at up to 68-amps, depending on how depleted the battery is.
With the large difference in battery costs and a large number of manufacturers, as Andy pointed out, will the vendor will disappear in a couple of years?
Most of these batteries are built-in Asia, from unknown companies. The odds are many will be gone in a year or two.
Paying more for a brand name, with a track record and good customer service, maybe the cheapest way to proceed.
Larry
p.s. the Renogy 100AH battery uses soft-pack cell technology - may be fine, but uncommon. Will Prowse has a youtube teardown of it. Not sure if the 200AH would use the same technology
The picture of the 200AH on the Renogy site shows what look like prismatic cells, not the pouch cells of the 100AH unit Prowse had.
"Battleborn claims their batteries can be connected to the alternator without harm."
Having spent a lot of time reading Battle Born's datasheets and manuals, and after watching an extended interview with their CEO, I get the feeling that they are pushing the "just drop it in" angle pretty hard, glossing over any potential problems. Maybe I'm a cynic, but I would not take that claim too seriously.
Battleborn claims their batteries can be connected to the alternator without harm.
If retaining the original isolator wiring and isolator (or relay), I doubt if the 10-gauge wiring can pass enough amperage to damage the alternator. This could make the DC to DC converter an unnecessary expense.
I'll do the conversion, then measure the alternator amperage with a mostly discharged house battery. If the current is less than, say, 50 amps, I'll stay with the direct charging from the alternator. As for brand names, Renogy is a US company that's been around for 10+ years, long enough for me to think they will be around 5-10 years from now.
Battleborn claims their batteries can be connected to the alternator without harm.
They are correct, it won’t harm the battery but if you connect an alternator to a low resistance load for any length of time something is gonna pop. At the very least aim a heat gun at the alternator. I don’t think my LD has a circuit breaker on the charging line and the wire is very heavy. Properly instrumented you could give it a try.
We could all learn something.
I disconnected the alternator from the coach electrical system the day AM Solar completed my system and warned me of the potential alternator damage.
That was September 2015, and it turns out that I've never needed the alternator boost. On very rare occasions I've topped up from the 4K generator or shore power, the panels suffice 98% of the time.
Give it a try without the converter and see if it's needed, if so it's simple to add later.
Steve
I disconnected the alternator from the coach electrical system the day AM Solar completed my system and warned me of the potential alternator damage.
That was September 2015, and it turns out that I've never needed the alternator boost. On very rare occasions I've topped up from the 4K generator or shore power, the panels suffice 98% of the time.
Give it a try without the converter and see if it's needed, if so it's simple to add later. Steve
Excellent plan! I'll do it.
Apropos of what Steve said: Long ago I disabled Skylark's isolator and substituted a big Blue Sea switch. When turned on, it combined the house and engine batteries, and set a little red LED to flashing as a reminder. (It may sound like a dumb idea to disable an automatic system and go manual instead, but I've seen and read about too many isolator failures. That heavy-duty switch was never going to fail.)
Anyway, my point is this: I found that I very rarely had any need to turn it on. Just as Steve said, my solar panels (500-600 watts on the roof) took care of the batteries most of the time, with very occasional help from the generator. If I were putting lithium batteries in a midbath today, I wouldn't even bother hooking up the line from the alternator.
That said, I am planning to install a Victron Orion 30A DC-to-DC charger in my Airstream, powered by a line from my truck. Why? Because unlike my LD, the Airstream has no built-in generator... and I haven't yet gotten around to installing solar panels on the roof. This setup will let me use the truck as a generator in an emergency.
Hi Andy; The difference in price was a few bucks between the 40 and 60 A Renogy boost converter. With the low current mode (LC), and the ability to manually control (dash switch, defaults to off) any charging (+D), It also isolates the chassis battery and house battery. The 2015 LD's and possibly earlier did away with the voltage drop diode isolator. They come now with a large rated relay. 300A capacity, 500A surge, that parallels the batteries when the engine is running. Much higher tech, and modern designed relays have improved a lot since the 'old days'.
The wire going to the battery box in my TK is #4, and I need to add a return ground chassis wire that doesn't go through my battery shunt. The output of the DC/DC booster does go through the shunt, and the grounds are isolated between input and output.
The Victron Cyrix combiner Cyrix Battery Combiners - Victron Energy (https://www.victronenergy.com/battery-isolators-and-combiners/cyrix-battery-combiners) has a mechanical relay that turns itself on and off by a microprocessor measuring time and voltage. The problem with that is there is no monitoring of the alternator current, and the entire engine/chassis system voltage changes to provide charging to the house batteries. The house batteries need 14.6 volts to charge, not good for the WLA chassis battery. I assume it shuts off (opens up) when the engine is stopped.
The BattleBorn isolator LiFePO4 Battery Isolation Manager (BIM) | Battle Born Batteries (https://battlebornbatteries.com/product/lifepo4-battery-isolation-manager/?gclid=Cj0KCQiArt6PBhCoARIsAMF5waiZINCnMsV_0pJ0YqD5mdvOGYPZNYdb1QWMGXhBxD3D7S9H7zvV3IYaAneoEALw_wcB) is also a mechanical relay that turns itself on and off on a fixed duty cycle. Well the duty cycle does check voltage output of the alternator / chassis battery / house battery condition. Also the engine and entire chassis voltage goes up and down when the relay cycles. It costs almost as much as the Renogy booster.
Both the Cyrix and BattleBorn BIM are much smaller, and can take 'under the hood' conditions. Maybe I should have gone that way. (not that there is much room available under the hood). If the Renogy doesn't work the way I want, I can switch things around. A work in progress.
Should the right used MB show up, I'm learning a lot on how to do this all. (Maybe again.) When it is all working properly I'll post a full description of what worked, with pictures. RonB
p.s. The added weight of new panels, wiring, booster and inverter is still under the 34 pounds of removed lead acid batteries( 65x2 vs. 48x2), old solar panels, (48Wx3 vs. 100Wx5) and removed battery drawer slide. Weight change about nil.
This discussion points out a dilemma for me. At the moment, our alternator and batteries are connected via a diode battery isolator. This type has a separate terminal for the alternator output which has no voltage present with the engine off. I have a modified-sine-wave inverter wired to power the fridge on AC while driving. This inverter is active through a relay to the chassis battery connection of the isolator, which is triggered by a connection to the alternator terminal of the isolator. This allows the inverter to remain off until the alternator is spinning and generating enough voltage. Since all the lithium - alternator interfaces require connecting the alternator output to the chassis battery, I would have to move my trigger point to the ignition switch - less desirable for several reasons.
For the time being, I will play wait-and-see on adding any of these aftermarket devices, with the possible option of simply tripping the 100A breaker in the battery box to eliminate alternator charging. Two Battleborn BBGC2 mounted in the existing battery tray.
Steve
Hi Steve; Your 2004 is pretty close to my '99. Under the hood is the wiring and fuses for the entertainment radio, and CB radio. They are connected to the #4 wire under the hood connected to the diode isolator house battery terminal, which isn't powered by the chassis battery, but is to the house batteries. I got the reverse camera from LD that is wired to be on in 'accessory' essentially just when the engine is on. I used that wire to power my dash USB and TST tire monitor. That wire supplies power to the reverse lights. I think another switch in series at the transmission selector turns those on. You could use that wire, under the steering wheel, to power an isolator relay. I have to remember not to use the other accessory position, since that enables the power windows. One cat was smart enough to use the window switch to escape the motorhome. (Long chase ensued at midnight at Hurkey Creek in 40 degree weather).
I plan to run the refrigerator on a small 400W inverter, powered behind the side access panel by the wire LD supplies (8 ga) to that area from the house battery. It would be enabled by that same signal. How do you keep the 'fridge from trying to light the gas flame when it loses 120 VAC from the inverter? Seems like that would defeat the purpose when filling at a gas station. I was going to turn off all 12v to the fridge during fueling to keep it idle. RonB.
Ron, I don't think your inverter will work - our fridge draws at least 500W. I use one of 850W from Harbor Freight. The fridge does switch to gas with the engine off - the oem fridge board had a 20 sec delay, enough time to launch to the back of the coach to turn the fridge off. Our current Dinosaur board has no delay, so I switch before turning off the engine. Just have to remember to turn it back on. Note the big issue is auto-switching the fridge socket between shorepower/gen and the inverter. After a failed homemade relay fiasco that smoked the first inverter, I installed another transfer switch identical to the gen transfer switch to do the job, inverter-priority. In a couple years use, the system has worked flawlessly.
After the battery conversion, I installed a 2200W sine wave inverter to allow powering the nuker and a hair dryer as needed for brief periods. A 30-sec run to warm coffee draws 157A and uses 1.1AH of charge. For that I use a manual transfer switch break-before-make to switch the 30A breaker. With the inverter enabled, I turn off the converter and switch the fridge to gas only. For smaller jobs I have a 300W sine wave inverter that plugs in as needed.
Steve
I plan to run the refrigerator on a small 400W inverter, powered behind the side access panel by the wire LD supplies (8 ga) to that area from the house battery. It would be enabled by that same signal. How do you keep the 'fridge from trying to light the gas flame when it loses 120 VAC from the inverter? Seems like that would defeat the purpose when filling at a gas station. I was going to turn off all 12v to the fridge during fueling to keep it idle. RonB.
The way you solve that is to put a relay controlled by the alternator output line in the line to the AC heater. When the alternator output line goes to 0 volts the relay opens up and the high 12 volt current to the inverter drops to the standby current. The refrigerator still thinks it is running on AC and does not switch to propane. The tough part is getting the alternator output line to the added relay in the fridge compartment.
I have a 3-way fridge and do that with the 12 volt power to the 12 volt heater. Works very well for gas stops. The alternator output line was added when the unit was built.
[quote author=Steve link= 8)
For the time being, I will play wait-and-see on adding any of these aftermarket devices, with the possible option of simply tripping the 100A breaker in the battery box to eliminate alternator charging. Two Battleborn BBGC2 mounted in the existing battery tray.
[/quote]
Have you tried discharging the battery and then charging it with the alternator only, measuring the current flow at the same time?
Larry
Have you tried discharging the battery and then charging it with the alternator only, measuring the current flow at the same time?
Larry
Nope. Discharging 200 AH requires more time than I have been able to devote to being in the rig yet. I DO know that with about 95% charge that I saw over 50A from the alternator.
Steve
That relay that Lazy Daze uses to connect the chassis battery to the house batteries so the alternator can charge both is a White Rodgers 586-108111. Rev A, 15 volt coil. Rated for 200A continuous, 600A inrush. https://www.supplyhouse.com/White-Rodgers-586-108111-Solenoid-SPNO-15-VDC-Isolated-Coil-Normally-Open-Continuous-Contact-Rating-200-Amps-Inrush-600-Amps?gclid=Cj0KCQiA0eOPBhCGARIsAFIwTs4gQws6LzxHDOujEFj9i1F0ccfuzbDUgO1hi70607__L02wturKK7kaAju_EALw_wcB
I notice that they want it mounted vertically, and it lives in the engine compartment. It could also be used as an emergency start relay to connect the house battery bank to the chassis battery to start the engine. A short duration push button to connect and start. I inherited this one from Kent when he had his coach upgraded to LiF by AM Solar.
You could call Todd Miller at LD to find out where they get the signal to activate it. RonB
This tech talk is mind numbing for the beginner I am. I was not told at LD when they installed a couple of AGMs how to care for them. Repeatedly draining them has rendered them unable to hold a charge for long. Purchased two Amperetime 12v 100 Ah and was going to just drop them in. Not so fast. It may or may not damage the '05 E450's alternator, I may or may not need a DC to DC charger which may or may not overheat, the onan generator may or may not fully charge them, and the 220 watts of solar panels may or may not be enough to charge them either and the whole godamn thing might or might not
burst into flames if I dont install the proper isolating diode flowing through a double ought cable that y's to all the components simultaneously during low voltage charging but not high voltage charging which requires a completely different fix. WTF? Does anyone have simple solutions for the simple minded?
This tech talk is mind numbing for the beginner I am. I was not told at LD when they installed a couple of AGMs how to care for them. Repeatedly draining them has rendered them unable to hold a charge for long. Purchased two Amperetime 12v 100 Ah and was going to just drop them in. Not so fast. It may or may not damage the '05 E450's alternator, I may or may not need a DC to DC charger which may or may not overheat, the onan generator may or may not fully charge them, and the 220 watts of solar panels may or may not be enough to charge them either and the whole godamn thing might or might not
burst into flames if I dont install the proper isolating diode flowing through a double ought cable that y's to all the components simultaneously during low voltage charging but not high voltage charging which requires a completely different fix. WTF? Does anyone have simple solutions for the simple minded?
We don't have simple solutions for folks who ask questions on this forum in an uncivil manner. If you would like to chill out for a while, count to ten and rephrase your question, someone will be glad to help you.
Chris
The technical discussions here are between Lazy Daze enthusiasts who are working to understand, and help others understand, the technical complexity themselves, because they are interested, or because they can spend their time in order to save money.
Would engaging a shop that handles all of the technical complexity be a solution? I hear good things about AM Solar, and there must be other shops around the country skilled in integrating batteries, chargers, etc. to craft an effective solution.
Annp,
I'm tend to be as guilty as anyone of overthinking this stuff, so let's simplify things.
Without any DC-DC converter or relay or diode, or anything linking the chassis and coach systems:
A) You will not harm your alternator as it will remain isolated from the coach.
B) Your coach batteries will eventually charge via either the solar or the coach generator. And Lithium batteries don't require a full charge every cycle as lead batteries do, just keep them above 20% or so.
C) You'll have at least one fewer electrical device to burst into flames, or fail in any manner.
D) You've saved some money and simplified the system.
If you later decide you need the boost from your alternator, you can always add that subsystem later once you feel better informed and have determined that it's actually needed.
I think you're on the right path going with solar and the LiFePO4 batteries. Despite what we paid over six years ago for our setup, it's possibly the best investment we've made on our LD and I have a feeling you'll eventually feel the same way.
Steve
Annp,
I'm tend to be as guilty as anyone of overthinking this stuff, so let's simplify things.
Without any DC-DC converter or relay or diode, or anything linking the chassis and coach systems:
A) You will not harm your alternator as it will remain isolated from the coach.
B) Your coach batteries will eventually charge via either the solar or the coach generator. And Lithium batteries don't require a full charge every cycle as lead batteries do, just keep them above 20% or so.
C) You'll have at least one fewer electrical device to burst into flames, or fail in any manner.
D) You've saved some money and simplified the system.
If you later decide you need the boost from your alternator, you can always add that subsystem later once you feel better informed and have determined that it's actually needed.
I think you're on the right path going with solar and the LiFePO4 batteries. Despite what we paid over six years ago for our setup, it's possibly the best investment we've made on our LD and I have a feeling you'll eventually feel the same way.
Steve
Agreed.
May as well keep the original batteries and put the lithiums inside where they belong. All you need is a marine battery switch to choose whether you power the coach from lithium or FLA. This is mentioned in a previous post.
This adds 210 AH to total power available and redundancy.
Mine has more than that: FLA charged from lithium, charging lithium from 120 amps of AC charger rather than converter. Solar charges whichever battery bank is powering the coach. These enhancements are not necessary.
When I had 200AH of lithium I used lithium for entertainment (satellite TV, DVD, now Starlink) and FLA for the furnace. (night)
Ann, I like Steve's advice: disconnect the alternator charging line and just use your solar panels and (when necessary) generator to charge the new batteries. That will eliminate a lot of your worries.
A couple of things to keep in mind. First, lithium batteries don't like temperature extremes. They'll be damaged if charged at temperatures below 32° F (0 ° C). Ampere Time's built-in circuitry protects the battery against "overcharge, over-discharge, overcurrent, and short circuit," but they don't say anything about preventing damage from charging when freezing or colder. So if you're going to mount these in an outside battery compartment (you didn't say what model/floorplan you have), you need to be very conscious of that.
You can do a couple of things to reduce the risk. Since lithium batteries don't need venting, you can block the vents on that external battery compartment door to keep out cold air. Do it with an insulating material such as Reflectix. And consider cutting an opening in the inner wall of that compartment, so that in cold weather, some of the warmth of the interior will get through.
Moving the lithium batteries indoors, as Harry suggested, would be even better from a temperature standpoint... but that's a major modification that you may not want to undertake. And running dual sets of batteries as he does is not simple (as I believe he recently commented elsewhere).
Second, if your '05 Lazy Daze has the original converter/charger, that's not the best (or fastest) way to charge lithium batteries. You may want to consider having it replaced with a more "intelligent" converter from Progressive Dynamics. You can find recommendations for which model is best elsewhere in these discussion threads. It will be kinder to your batteries, and will also charge them faster, meaning less generator run time.
One last thing: it's not hard to damage batteries if you don't have a good idea of their state of charge, and the multicolored LEDs that Lazy Daze provided in your '05 are about as useful as a gas gauge that only reads FULL or EMPTY. I'd strongly recommend adding a good battery monitor such as Victron's BMV-712 (https://www.amazon.com/Victron-Energy-MONITOR-VTBMV-S-BMV-712-Battery/dp/B075RTSTKS/ref=sr_1_3). It will give you an accurate reading of the battery's level, so that you can know when you're getting dangerously low.
This electrical stuff can sound complicated and intimidating. Many of us are still figuring it out in our own ways. If you prefer not to deal with it on your own, AM Solar up in Oregon has a good reputation, as Keith mentioned.
We don't have simple solutions for folks who ask questions on this forum in an uncivil manner. If you would like to chill out for a while, count to ten and rephrase your question, someone will be glad to help you.
Chris
ANNP: Sorry for the harsh response. Obviously I did not feel your frustration. We try to approach problems and frustrations here on LDOF with simple questions, unladed with cursing. I'm hopeful our members can help you with your issues.
Chris
This tech talk is mind numbing for the beginner I am. I was not told at LD when they installed a couple of AGMs how to care for them. Repeatedly draining them has rendered them unable to hold a charge for long. Purchased two Amperetime 12v 100 Ah and was going to just drop them in. Not so fast. It may or may not damage the '05 E450's alternator, I may or may not need a DC to DC charger which may or may not overheat, the onan generator may or may not fully charge them, and the 220 watts of solar panels may or may not be enough to charge them either and the whole godamn thing might or might not
burst into flames if I dont install the proper isolating diode flowing through a double ought cable that y's to all the components simultaneously during low voltage charging but not high voltage charging which requires a completely different fix. WTF? Does anyone have simple solutions for the simple minded?
This tech talk is mind numbing for the beginner I am. I was not told at LD when they installed a couple of AGMs how to care for them. Repeatedly draining them has rendered them unable to hold a charge for long. Purchased two Amperetime 12v 100 Ah and was going to just drop them in. Not so fast. It may or may not damage the '05 E450's alternator, I may or may not need a DC to DC charger which may or may not overheat, the onan generator may or may not fully charge them, and the 220 watts of solar panels may or may not be enough to charge them either and the whole godamn thing might or might not
burst into flames if I dont install the proper isolating diode flowing through a double ought cable that y's to all the components simultaneously during low voltage charging but not high voltage charging which requires a completely different fix. WTF? Does anyone have simple solutions for the simple minded?
To put it bluntly you didn’t have the tools or knowledge to manage your AGMs properly. You certainly don’t have the tools or knowledge to manage lithiums properly.
My suggestion is to put them in the back room, install two flooded lead acid batteries and a shunt type battery monitor (Bogart Trimetric or Victron) and learn how to use it.
If that doesn’t work for you then hire a shop like AM solar to install your lithiums and battery monitor and explain how to use it.
Ann has or had a 2005 MB, but before these posts here her last post on the group was 9 years ago. Repeating identical vulgar posts twice in the same thread has to be a hacked user id...
Steve
No, the user id was not hacked, I'm Ann's husband Rod and i have apologized for not controlling my frustration. The double posting was due to my incompetence. I wasn't sure if it had posted. Sorry if anybodys feathers got ruffled but exactly how "vulgar" was it? Not terribly in my opinion so perhaps the offended should loosen the grip on their pearls.
In the meantime it looks like my two choices are install the batteries and disconnect the alternator from the coach and rely on solar and genset to charge or install new components both in the truck and coach. The solar installation by AM Solar is first class and having a shop do the latter choice is our preference. There must be a reputable shop here in SoCal. Any reccomendations?
"you didn’t have the tools or knowledge to manage your AGMs properly"
True. But as Rod pointed out, Lazy Daze didn't give them either the tools (a useful battery monitor) or the knowledge. I don't know what the factory is installing nowadays, but back in 2005 the three "idiot lights" provided for battery status were nowhere near adequate for managing batteries of any kind.
I remember vividly how extremely frustrated I was in the early days with Gertie, with nothing to go on but those colored lights and a voltmeter. I had more than 500 watts of solar panels and four group 27 batteries, yet I kept running out of power... and I couldn't figure out why! It was driving me crazy.
It wasn't until I installed an amp-counting battery monitor (Xantrex XBM, an older unit similar to the Victron BMV series) that I began to get a handle on managing my 12 V power. So I can sympathize with Rod and Ann's frustration.
Hi Rod; Generally speaking you can just 'drop in' the Ampere LiF batteries without any other modifications. It won't catch on fire or burn up your alternator. That video that Victron uses to scare you not to hook up directly to an alternator, isn't representative of automotive alternators. It should work fine, but won't be optimum. The small details we've been discussing are to get better power delivery and charging, to make the expense of the batteries pay off better.
As stated previously the big hazard is pushing power into the batteries if they are below 32 degrees. That will damage them permanently. The converter may not have a high enough voltage output to charge the batteries very well. Likewise the solar. The converter and solar are optimized for lead acid. Shore power and generator go through the converter. It also is oriented to lead acid. It won't hurt anything, but it may not work very well.
My first step was to install a newer converter that by jumper could also run LiF batteries. The R3000i solar controller can be manually re-programmed to output higher voltages to fit the LiF profile.
With lead acid, my alternator routinely provided 14.6v to 14.8 volts (my scan gauge display). That should provide enough voltage to recharge the LiF battery. By using your installed #4 gauge wiring, it may provide enough voltage drop to limit current from being excessive. My '99 Ford E350 had a 100 A breaker in the charge line. If it opens for your application (and needs resetting) then you might be overstressing the alternator.
Andy is correct. You need to have a way to monitor the battery's charge status. The built in BMS may shut the battery(s) down when it is fully charged. That protects the battery, but doesn't provide power to the coach either. When it is nearly discharged the BMS will turn the LiF off, again to protect itself. But it may be at some un-predictable time, if you aren't expecting that to happen. LiF's don't change output voltage much as they deplete, normally a good thing. But it makes it hard to track the charge amount by monitoring the output voltage.
Installing a meter shunt and having a meter to show your charge status, will make it easier to anticipate how your new batteries are behaving. That also is a good thing for lead acid batteries and Lazy Daze should have provided that. It would have helped manage the AGM's better then. RonB
This looks to be a good basic meter that could be used to monitor your batteries. Amazon.com: Renogy 500A Battery Monitor, High and Low Voltage Programmable... (https://www.amazon.com/Renogy-500A-Battery-Monitor-Programmable/dp/B07RP5B5P7/ref=pd_bxgy_1/143-3126042-2241000?pd_rd_w=Z9Ui5&pf_rd_p=6b3eefea-7b16-43e9-bc45-2e332cbf99da&pf_rd_r=ZRW7B7N90TA4HS4WNQP4&pd_rd_r=f8553cfd-abc7-485a-b3a3-3bc34147c167&pd_rd_wg=tKCQe&pd_rd_i=B07RP5B5P7&psc=1)
The price is reasonable and will tell you what is going on with your new batteries. RonB
Looks like a less expensive alternative to the Victron BMV series battery monitors that many of us use. If anybody buys one of these, please let the group know how you like it.
The beauty of the Renergy is its surface-mounted monitor, not requiring drilling a 2" diameter hole in a wall.
This makes the installation so much easier than the Victron and other battery monitors.
Larry