Want to put 2 x 200ah lithium batteries in caravan do they need a lithium charger
So confused, also how much solar would I need to run for them
Cheers
Ken
Whenarewethere said
04:47 PM Jul 18, 2022
They at least need a charger that has a lithium setting. Once lithium batteries are charged you have to stop charging. No float charging like lead acid.
Spend the time & read this very long article to get your head around lithium. You will save a fortune in stuffups. Look at the amortised long term. It it too expensive to ruin a lithium setup.
Once you have read all that then you should be well ahead of the game.
TimTim said
05:08 PM Jul 18, 2022
shaken wrote:
Want to put 2 x 200ah lithium batteries in caravan do they need a lithium charger So confused, also how much solar would I need to run for them Cheers Ken
Hi Shaken, that is a nice lot of lithium. You will need an MPPT solar controller and enough solar panels to replace what you use each day. Firstly it is best to do a power audit to determine what you are using. Are you planning on using an inverter?
Im in Mykonos at the moment so my replies will be delayed because of time difference.
shaken said
05:24 PM Jul 18, 2022
Hi guys
Would like to run a 2000 to 3000w inverter
Thanks for your input
Ken
Whenarewethere said
05:34 PM Jul 18, 2022
Agree.
Also depends on your type of travel. If you move regularly a DC-DC charger maybe all that's needed. Our last 3 month holiday we didn't use solar once as we only stayed in one location for 4 days. We theoretically have 7 days reserve. Using gel batteries.
It is a whole of system setup. Length of stay. Latitude. Trees. How much reserve you are comfortable with before using fossil fuel.
TimTim said
06:06 AM Jul 19, 2022
shaken wrote:
Hi guys Would like to run a 2000 to 3000w inverter Thanks for your input Ken
Hi Ken, WAWT has given you some good links and in that DickO (Richard) has provided great information on lithium batteries. Is this a DIY project for which you are looking to buy the components or are you having someone install a system for you?
Many would say put as much solar on your roof as you reasonably can. In my case the van manufacturer was pushing for only one 160w panel and I fought to get two installed for 320w but when I get back I will be installing a third to give me 480w. I also have a seperate Anderson plug connected to my batteries which i can connect another solar controller and a number of the various portable panels that i have to supplement the battery charging. They are great if you have limited roof area or if you are in shaded areas.
A DC/DC charger is great for charging as you drive to your next stop and there are units that incorporate the DC/DC charger, solar controller, mains charger and battery isolator etc in one unit. I have a Redarc Manager 30 which is expensive but there are numerous other similar products out there or alternatively you can buy the seperate components.
Have you looked at what 200Ah batteries you will be getting because there are differences in the discharge rates. Some will have a maximum continuous discharge rate of 100A (0.5C) and others 200A (1C).
Whenarewethere said
07:52 AM Jul 19, 2022
TimTim has highlighted a lot of important issues. Critically from the battery's point of view, its C rating for charging & discharging. A lot of cheaper batteries have pretty low C rating & you may depending on your load need a third battery.
It is also worth working out your maximum load & having fuses or circuit breakers on each of the batteries just in case you get a runaway discharge.
You say 2000 to 3000 watt inverter. You are better to work out what you actually need. It actually would be better to have a small dedicated inverter for the fridge & the odd LED light.
A second large inverter to run a microwave etc. The larger the inverter the more standby energy is used. Some of the high quality inverters like Victron have a Eco mode which monitors for a load. One of their small inverters for the fridge would be a good investment to run a fridge as economically as possible, it is on & off 24 hours a day.
Look at a Birko 750 watt kettle, it is always better to have a smaller load over a longer period. Chuck out the 2200 watt kettle.
A bit of planning with energy usage like running only one heavy load like microwave (look at input not output) at a time will help your system a lot.
The longer you camp in one location the more solar you will need, to a point. Factor in inclement weather. You then need options for charging.
Whenarewethere said
07:57 AM Jul 19, 2022
A basic rule of thumb for inverters is divide the wattage by 10 for amps which factors in inefficiencies.
So a 3000 watt inverter / 10 = 300 amps
It's a lot of amps even for a large system.
shaken said
04:01 PM Jul 22, 2022
Is true that some lithium batteries can not be in parallel or series
TimTim said
04:40 PM Jul 22, 2022
shaken wrote:
Is true that some lithium batteries can not be in parallel or series
Whether lithium batteries can be put in parallel or series is generally dependent on the quality of the BMS installed. Avoid any that state they cant be. I would also recommend, although it is not critical, that you get batteries that have a Bluetooth function that you are able to monitor the cells. It isnt so much you want to be looking at each day but if there is an issued that arises you are able to see how the cells are. However, the vast majority of issues with Lithium batteries are with the BMS and not the cells.
If you post here what batteries you are looking at I am sure a good few people including myself will give you our thoughts. You can pay top price for batteries or mid price and you will get the same quality cells in a different case.
Dick0 said
11:06 AM Jul 23, 2022
Hi shaken and welcome.
Do a search on this forum for lithium batteries as this topic has been covered extensively.
I don't want to sound negative but plenty of info on this topic on forum.
Covers solar panels, solar chargers, 240v chargers, lithium battery types, connecting several batteries, inverters and information guides etc.
They at least need a charger that has a lithium setting. Once lithium batteries are charged you have to stop charging. No float charging like lead acid.
Spend the time & read this very long article to get your head around lithium. You will save a fortune in stuffups. Look at the amortised long term. It it too expensive to ruin a lithium setup.
https://thegreynomads.activeboard.com/t67732755/lithium-batteries-charging-discharging-balancing/
Once you have read all that then you should be well ahead of the game.
Hi Shaken, that is a nice lot of lithium. You will need an MPPT solar controller and enough solar panels to replace what you use each day. Firstly it is best to do a power audit to determine what you are using. Are you planning on using an inverter?
Im in Mykonos at the moment so my replies will be delayed because of time difference.
Agree.
Also depends on your type of travel. If you move regularly a DC-DC charger maybe all that's needed. Our last 3 month holiday we didn't use solar once as we only stayed in one location for 4 days. We theoretically have 7 days reserve. Using gel batteries.
It is a whole of system setup. Length of stay. Latitude. Trees. How much reserve you are comfortable with before using fossil fuel.
Hi Ken, WAWT has given you some good links and in that DickO (Richard) has provided great information on lithium batteries. Is this a DIY project for which you are looking to buy the components or are you having someone install a system for you?
Many would say put as much solar on your roof as you reasonably can. In my case the van manufacturer was pushing for only one 160w panel and I fought to get two installed for 320w but when I get back I will be installing a third to give me 480w. I also have a seperate Anderson plug connected to my batteries which i can connect another solar controller and a number of the various portable panels that i have to supplement the battery charging. They are great if you have limited roof area or if you are in shaded areas.
A DC/DC charger is great for charging as you drive to your next stop and there are units that incorporate the DC/DC charger, solar controller, mains charger and battery isolator etc in one unit. I have a Redarc Manager 30 which is expensive but there are numerous other similar products out there or alternatively you can buy the seperate components.
Have you looked at what 200Ah batteries you will be getting because there are differences in the discharge rates. Some will have a maximum continuous discharge rate of 100A (0.5C) and others 200A (1C).
TimTim has highlighted a lot of important issues. Critically from the battery's point of view, its C rating for charging & discharging. A lot of cheaper batteries have pretty low C rating & you may depending on your load need a third battery.
It is also worth working out your maximum load & having fuses or circuit breakers on each of the batteries just in case you get a runaway discharge.
You say 2000 to 3000 watt inverter. You are better to work out what you actually need. It actually would be better to have a small dedicated inverter for the fridge & the odd LED light.
A second large inverter to run a microwave etc. The larger the inverter the more standby energy is used. Some of the high quality inverters like Victron have a Eco mode which monitors for a load. One of their small inverters for the fridge would be a good investment to run a fridge as economically as possible, it is on & off 24 hours a day.
Look at a Birko 750 watt kettle, it is always better to have a smaller load over a longer period. Chuck out the 2200 watt kettle.
A bit of planning with energy usage like running only one heavy load like microwave (look at input not output) at a time will help your system a lot.
The longer you camp in one location the more solar you will need, to a point. Factor in inclement weather. You then need options for charging.
A basic rule of thumb for inverters is divide the wattage by 10 for amps which factors in inefficiencies.
So a 3000 watt inverter / 10 = 300 amps
It's a lot of amps even for a large system.
Whether lithium batteries can be put in parallel or series is generally dependent on the quality of the BMS installed. Avoid any that state they cant be. I would also recommend, although it is not critical, that you get batteries that have a Bluetooth function that you are able to monitor the cells. It isnt so much you want to be looking at each day but if there is an issued that arises you are able to see how the cells are. However, the vast majority of issues with Lithium batteries are with the BMS and not the cells.
If you post here what batteries you are looking at I am sure a good few people including myself will give you our thoughts. You can pay top price for batteries or mid price and you will get the same quality cells in a different case.
Hi shaken and welcome.
Do a search on this forum for lithium batteries as this topic has been covered extensively.
I don't want to sound negative but plenty of info on this topic on forum.
Covers solar panels, solar chargers, 240v chargers, lithium battery types, connecting several batteries, inverters and information guides etc.