why i call Li fussy
Hi all, This doesn't cover all the concerns for me, but it does show at least some of them: https://youtu.be/_PgthByAYz4
Forum Discussion
Note that was -20C to + 5C when the charger changes over and starts charging- not 0C.
The Relion and Trojan Trillium blurbs mention you need to reduce the amps for charging when under 5C /40F. How much of a reduction? There is some controversy over how much this matters among guys on here. IMO the battery specs come first.
So it might be an issue for camping when it gets to 5C as the daily high and gets down to freezing at night (like here in the winter quite often), and the batts are outside.
Unfortunately, the battery spec guys don't say how you can reduce those amps. An RV converter has its rated amps (current limited), and it will do whatever the batteries will accept up to that many amps. You can't choose a lower amps setting.
If you knew the battery temperature when it is being charged, perhaps you can crank up the amps once it gets over 5C. Do you have a way to know the battery temp vs the ambient temp?
If you intend to use the battery AH to warm it up before it can be charged, you have to leave enough capacity in there to do that. So how many AH do you have to leave in? You sure don't want it to go below the BMS shut down during the heating up phase. Now you have no 12v in the rig! Now what?
To avoid all these scenarios, guys with LFP make sure they don't get into such a situation in the first place. They recharge sooner at a higher SOC. That can mean not using as much of the LFP capacity as they could in moderate temperatures.
Some portable chargers do have amps setting you can choose, like the old Vector models.
The Relion and Trojan Trillium blurbs mention you need to reduce the amps for charging when under 5C /40F. How much of a reduction? There is some controversy over how much this matters among guys on here. IMO the battery specs come first.
So it might be an issue for camping when it gets to 5C as the daily high and gets down to freezing at night (like here in the winter quite often), and the batts are outside.
Unfortunately, the battery spec guys don't say how you can reduce those amps. An RV converter has its rated amps (current limited), and it will do whatever the batteries will accept up to that many amps. You can't choose a lower amps setting.
If you knew the battery temperature when it is being charged, perhaps you can crank up the amps once it gets over 5C. Do you have a way to know the battery temp vs the ambient temp?
If you intend to use the battery AH to warm it up before it can be charged, you have to leave enough capacity in there to do that. So how many AH do you have to leave in? You sure don't want it to go below the BMS shut down during the heating up phase. Now you have no 12v in the rig! Now what?
To avoid all these scenarios, guys with LFP make sure they don't get into such a situation in the first place. They recharge sooner at a higher SOC. That can mean not using as much of the LFP capacity as they could in moderate temperatures.
Some portable chargers do have amps setting you can choose, like the old Vector models.
