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Dual Cell charging with MAX1555

I need t o charge this dual cell battery. So there was this great charger chip called the MAX1555. But what was sad is that it said that the MAX1555 is a single cell charger. So I was wandering, since the dual cell battery has 2 charging wires, could i buy 2 MAX1555s and hook them up to each cell, Or would that not work. 

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Fascinating. I have the same question. I too have some MAX1555 samples from a previous scrapped project. I'm looking to charge a 7.4V 2500mah pack that has the usual two-wire power connector and the multi-wire Deans connector.  As far as "instant" charger solutions I was looking at the MAX745. It seems to fit the bill for me; 4A, 2+ cells, current limit/max voltage charge termination, etc. (and there are samples available). Maybe it would work for you too.

I'm still curious if I can wire up the battery to use a couple 1555s instead, since I have them laying around.

Well then is it possible you could help experiment for me, that would be really helpful. I want to get everything from sparkfun as One big order for my next project so i don't pay another shipping fee. It'd be cool if it works for you. Also it says the Max745 is for lithium ion, I have a lithium polymer battery i need to charge. 


Thanks! :D

Li-po's use the same 3.7V lithium ion chemistry. The normal Li+ batteries use liquid to suspend the electrolyte. Li-po batteries do away with the liquid and impregnate a polymer layer with the electrolyte, if I recall the details correctly. Just to ease your mind...


You can see the MAX745 is used for both Li+ and Li-po as listed under their parametric search.

I'm not sure if I'll be much assistance to you for this experiment. This Li-po driven bot I'd be working on is... eh... maybe in position #4 as far as the robot project list goes. It's a good ways off seeing how long each robot takes me to build. I would also use the circuit to charge my RC heli's Li-po but I have to do the conversion from NiMH to Li-po before that matters as well.

Also, I checked after I made my first RE: and I have the MAX1508s, not the MAX1555s. Just a couple more pins but still a single-cell Li-po charger. I will update if I happen to get distracted and work on any of this.

I asked my electronics teacher today and he said that it was safe to charge the two cells of a lipo battery separately.

Yes, that is no big deal, that's what a balance charger does. I could only think of setups that were a PITA due to setting up two chargers instead of just one for series charging. Maybe a MAX745 to do the fast charging, two 1555s or similar to do balance charging, and a microprocessor to run the whole show. That would be a nifty PITA DIY charger project. If you could stay under a budget of $100 it would almost make fiscal sense too.