Skip the BMS (separate port) to charge Li-ion cell of my solar bike from MPPT

[amisi]

Hi,

I have 240 Wc Solar Panel with a MPPT boost (CTKEV300). The battery of my e-bike is 19.2 Ah 36 V (4p10s) and the BMS on it is 5 amp recharging, which I find quite conservative for 19.2 Ah Li-Ion. I think I could charge 6.5- 7 Amp without damaging the cells. (36*5 = 180 W, 42*5 = 205 W) so more sun power than what can BMS do).

First, do you agree with that or would advise me to buy a new battery with more capacity for my 240 Wc Solar Panel ?

I do not know the exact spec of the BMS and head charging, if they're fused, cut off and how to restart it when it happen for I have not open the battery yet for the warranty.

I have two solutions :

- Buying a new BMS with over 7 amp capacity for the charge and replace the current BMS. My last solution, because I plan a trip with this bike for several weeks very soon.

- Charging by output. Solar panel probably will never produce more than 260 W at peak sun and my MPPT can have a limit at 42 V. Do I take some risk for me or for the battery in this case ?

If None of these, solutions is good, I could limit the max current by some ways but that is not my main idea.

Thank you for your opinion

 

[upnorthandpersonal]

Consider that you won't get the 240W out of the panel except in perfect conditions (i.e. never). You can count at around 80% in near optimal real use case, so the BMS you have is fine.

 

[Supervstech]

With LiNMC conservative is the way to go.
Fire is a bad thing.

 

[amisi]

Consider that you won't get the 240W out of the panel except in perfect conditions (i.e. never). You can count at around 80% in near optimal real use case, so the BMS you have is fine.

I would prefer to be confident with that information. I might go in area where the sun lights a lot (South of spain, Morocco) so that could happen . And I cannot test in those area because I am not there at the moment

 

[upnorthandpersonal]

I would prefer to be confident with that information. I might go in area where the sun lights a lot (South of spain, Morocco) so that could happen . And I cannot test in those area because I am not there at the moment

It's also hot in those places, so your panel efficiency will drop significantly.