hi
i want to power my portable speaker by 8 lithium ion batteries.these batteries are in series and i want charge them with 8 "tp4056" module.but i think i can't connect each module to each battery (in fact series them).
so how can i do that?
i want to power my portable speaker by 8 lithium ion batteries.these batteries are in series and i want charge them with 8 "tp4056" module.but i think i can't connect each module to each battery (in fact series them).
so how can i do that?
8 stack x 3.2 v is 25.2 v, which is a weird voltage for a commercial charger. You may have to build it.
cells can go up to 4.2 v @ full charge, so 8x that is 33.6 v
You might be able to get away with a 32 v golf cart/forklift charger, but those are not cheap. Those don't shut off at 33.6 v either, you'd have to build your own voltage detection shutoff with a triac or relay or something.
I built the pictured charger for 13 stack LiIon batteries, nominal 48 v, shut off @ 54.2 v . Uses a 47.5 vac nominal transformer, with a diode stack for peak voltage shutoff. You'd need a lower voltage transformer. Realize peak transformer voltage is (nominal voltage * 1.4) -1.4v so for 32.6 v a 24 v transformer would work.
The CCS in the picture is for 14 parallel cells, 4 A max, so you would want a lower CCS value for a single stack of cells. One cell won't take 4 A charge current.
Warning, do your experimenting and charging outside. LiIon cells can catch fire charging, and the only thing that will put the fire out is a pile of dirt.
cells can go up to 4.2 v @ full charge, so 8x that is 33.6 v
You might be able to get away with a 32 v golf cart/forklift charger, but those are not cheap. Those don't shut off at 33.6 v either, you'd have to build your own voltage detection shutoff with a triac or relay or something.
I built the pictured charger for 13 stack LiIon batteries, nominal 48 v, shut off @ 54.2 v . Uses a 47.5 vac nominal transformer, with a diode stack for peak voltage shutoff. You'd need a lower voltage transformer. Realize peak transformer voltage is (nominal voltage * 1.4) -1.4v so for 32.6 v a 24 v transformer would work.
The CCS in the picture is for 14 parallel cells, 4 A max, so you would want a lower CCS value for a single stack of cells. One cell won't take 4 A charge current.
Warning, do your experimenting and charging outside. LiIon cells can catch fire charging, and the only thing that will put the fire out is a pile of dirt.
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I never felt good about lithium ion batteries - call me paranoid, but all the reports and videos I've seen of them exploding gives me the creeps.
Furthermore, the quality of them is questionable.
I'd sooner go with the old school time-tested and "trusted" lead-acid sealed batteries used in things like alarm systems and such.
Two 12 volt batteries in series make about the same voltage as needed, and charging them seperately isn't hard to impliment with a switching arrangement or relays.
Each battery can be charged at 13.2-13.8 volts.
Furthermore, the quality of them is questionable.
I'd sooner go with the old school time-tested and "trusted" lead-acid sealed batteries used in things like alarm systems and such.
Two 12 volt batteries in series make about the same voltage as needed, and charging them seperately isn't hard to impliment with a switching arrangement or relays.
Each battery can be charged at 13.2-13.8 volts.
thank you
what i realize is that you don't use a balancer and there is no wires between cells.just two wire one connect to first battery's negative pole and one to last battery's positive pole and all cells charge with a constant current.
am i right?do all cells charge safe?
My bike battery has 14 stacks, and a BMS (battery management system) to balance charge between the cells. The only connections are XT90 main out and XT60 charge in.
You talked about an 8 stack. If it is one cell stack, none parallel, you don't need a BMS. If it is several stacks parallel, you need a bms. The charger drawn goes to the charge input of the BMS.
BMS come from ***** and good luck getting any data on how they work. Some proprietary IC with no numbers. There is a FET for each stack to disconnect them as that stack reaches full charge.
24 v is a nominal scooter battery voltage, and you should be able to buy one of those on amazon/ali/ebay prebuilt with BMS. Good luck on getting one that works, I bought one pile of LiFePo4 trash from amazon and another from ebay. I know 3 trusted US vendors of 36 v & 48 v bike batteries, but those vendors are out of the 24v market. If you're in hong kong, EM3EV is trusted, but I'm not exporting my debit card number to a server not protected by the FBI money laundering enforcement.
You can get more data on liIon batteries somewhere on endlesssphere, but I don't participate there.
You talked about an 8 stack. If it is one cell stack, none parallel, you don't need a BMS. If it is several stacks parallel, you need a bms. The charger drawn goes to the charge input of the BMS.
BMS come from ***** and good luck getting any data on how they work. Some proprietary IC with no numbers. There is a FET for each stack to disconnect them as that stack reaches full charge.
24 v is a nominal scooter battery voltage, and you should be able to buy one of those on amazon/ali/ebay prebuilt with BMS. Good luck on getting one that works, I bought one pile of LiFePo4 trash from amazon and another from ebay. I know 3 trusted US vendors of 36 v & 48 v bike batteries, but those vendors are out of the 24v market. If you're in hong kong, EM3EV is trusted, but I'm not exporting my debit card number to a server not protected by the FBI money laundering enforcement.
You can get more data on liIon batteries somewhere on endlesssphere, but I don't participate there.
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