Battery marriage...needed or not? Testing starts soon.

[Mooch]

Finally getting started on determining whether we need to marry our batteries in multi-battery mods and, if we do, how well matched they need to be. I've had my own thoughts about this for quite a while but it's time for proof.

Using three RX200 battery sleds (no circuit boards), a datalogger, and a ton of batteries, I'll be trying out different combinations of batteries, battery positions, different levels of charge, etc., to see if any battery ever drops far enough in voltage to become damaged or brought below zero volts (which is dangerous).



You might have noticed the white batteries. They're "specials", high capacity batteries rated at 5A-10A. These, along with the other 1500mAh-3000mAh 20A-30A batteries (new, used, and damaged) will give the marriage theory a good workout.

It's going to take a few weeks to complete this testing but I'll post when I can as it proceeds.

 

[r77r7r]

Ty sir

 

[Jim_ MDP]

Cool beans. I bet it will take a good few weeks.

Not sure if I'm leaning toward wanting a surprising finding or not, but I'll be reading.

 

[DaveP]

I'm interested in seeing the outcome, Mooch. As an RX200S owner I'm curious about the battery voltage report you get when you turn off the RX200S with 5 clicks and then hold Fire, plus, and minus for a few seconds to get voltage readings. Every time I do that the 1 and 3 readings closely match. The middle #2 reading is a tenth or more less.

I've done that several times and then taken the batteries out and read them with a DVM. They all match on the DVM. I'm thinking that the RX200S is using power from a single battery to power the electronics to render the reading. If that's not it, then the digital voltmeter in the RX200S is miscalibrated. There's got to be a reason.

Things like that just bug me, being a technician type. I've heard that the RX200S can be used with 2 or 3 batteries, although I just pop 3 married cells in and vape.

 

[Jim_ MDP]

I understand that the RX200S can be used with 2 or 3 batteries, although I just pop 3 married cells in and vape.

Do you mean you own a new "2/3" ?
I've never seen that feature ascribed to the "S", nor any other 3-cell Reuleaux.

And Mooch posted that he's using the sleds alone... not the RX circuitry. No 5 clicky.

 

[DaveP]

Do you mean you own a new "2/3" ?

I've never seen that feature ascribed to the "S", nor any other 3-cell Reuleaux.

There were two questions in my OP. First was about the difference in voltage readings using the 3 button voltage display feature.

The other was about whether it was able to work with less than 3 batteries. I read somewhere about a 2 or 3 battery mod that can work at lower wattage with a battery removed. Shortly after posting that I remembered that it's a series device. Fewer cells would only work in parallel mode.

The RX200S couldn't do that wired in series.

 

[Jim_ MDP]

Correct on the series sleds... it's all or nothing.

There were two questions in my OP. First was about the difference in voltage readings using the 3 button voltage display feature.

I agree it's been annoying trying to nail down what the RXs were doing.
My early original would have one cell off by a tenth or two, just as you noted with yours.

We went round and round on that back when (10 months ago), but mine's been half borked for a couple months now and I just don't think about it anymore.

My point was... Mooch might wire up his test bed to be able to discretely read each cell, but without the RX board he won't be seeing the mismatched reading we all did with the full mod. No brain, no buttons... no clicky.

 

[DaveP]

Correct on the series sleds... it's all or nothing.



I agree it's been annoying trying to nail down what the RXs were doing.
My early original would have one cell off by a tenth or two, just as you noted with yours.

We went round and round on that back when (10 months ago), but mine's been half borked for a couple months now and I just don't think about it anymore.

My point was... Mooch might wire up his test bed to be able to discretely read each cell, but without the RX board he won't be seeing the mismatched reading we all did with the full mod. No brain, no buttons... no clicky.

The voltage thing on the diagnostic display makes me wonder if the out of range warning/shutdown feature on the RX200 and the RX200S is accurate. Inside the connector there has to be a wire going to an endpoint ground and 3 positive points on the batteries to monitor voltage levels.

I don't have my RX200S with me. I'm at the beach this week and only took mods I could fit in a pocket. I left the RX200S at home, but as I remember the center battery voltage was off by about .10v to .15v from the other two that were close matches in voltage.

 

[Jim_ MDP]

The voltage thing on the diagnostic display makes me wonder if the out of range warning/shutdown feature on the RX200 and the RX200S is accurate. Inside the connector there has to be a wire going to an endpoint ground and 3 positive points on the batteries to monitor voltage levels.

You should bring up the topic in the RX thread(s), it's probably a derail here.

Unless it turns out to be an inherent issue with the sled/wiring design, which Mooch will discover in the coming weeks.

 

[sonicbomb]

You are the Man Mooch

 

[B2L]

Finally getting started on determining whether we need to marry our batteries in multi-battery mods and, if we do, how well matched they need to be. I've had my own thoughts about this for quite a while but it's time for proof.

Using three RX200 battery sleds (no circuit boards), a datalogger, and a ton of batteries, I'll be trying out different combinations of batteries, battery positions, different levels of charge, etc., to see if any battery ever drops far enough in voltage to become damaged or brought below zero volts (which is dangerous).



You might have noticed the white batteries. They're "specials", high capacity batteries rated at 5A-10A. These, along with the other 1500mAh-3000mAh 20A-30A batteries (new, used, and damaged) will give the marriage theory a good workout.

It's going to take a few weeks to complete this testing but I'll post when I can as it proceeds.

 

[Phassat]

Go go Mooch

 

[h00ligan]

I can't wait for this. My impression is a good chip can rebalance in mod without issue and therefore it isn't. My impression of using two random batteries is poor performance. Not danger.

It seems most say the sky will fall if you use unmarried. I want to spit s married set because they're vtc5 and j can get more use out of them individually and replace with 25r but despite habit some beware 25r u could marry. They're not uncharged. Bother have been used pretty similar amounts I considered putting them in my boxer classic with yihi chip to see what would happen but I'll hold off as your testing is far more engaging and repeatable.

Thanks for all your battery work. It's been very helpful today for me in reprocessing what j need. I bought way too many 25r. :/.

I need the best high cap button top also. For mech.

Anyway. Subscribed !! Great

 

[sawlight]

Subscribing.

 

[ckquatt]

Subscribing.

Definitely! I've always wondered about this. I don't have any need for mods with more than one battery but I remember when stacking batteries was the thing to do, then ll of a sudden it wasn't. Everyone was told it was dangerous and never should be done.

I've always thought that battery marriage was something like that as well. Everybody says you HAVE to, but maybe we'll see that it's just a load of bunk.

Like I said, I don't have a dog in this fight, but the results will be interesting to see!

 

[sawlight]

Definitely! I've always wondered about this. I don't have any need for mods with more than one battery but I remember when stacking batteries was the thing to do, then ll of a sudden it wasn't. Everyone was told it was dangerous and never should be done.

I've always thought that battery marriage was something like that as well. Everybody says you HAVE to, but maybe we'll see that it's just a load of bunk.

Like I said, I don't have a dog in this fight, but the results will be interesting to see!

Well I've seen what happens to flashlights with mismatched batteries, even once with brand new CR123a batteries, it's not pretty! They don't push them anywhere near as hard as we do!

 

[h00ligan]

Well I've seen what happens to flashlights with mismatched batteries, even once with brand new CR123a batteries, it's not pretty! They don't push them anywhere near as hard as we do!

They also aren't using high tech regulation boards.

I don't doubt for s minute mech mods with batteries in series or parallel need marriage. I do think most modern mods can be used to balance batteries after the fact. Like I
Could take two disparate 659 and throw them in my boxer. Charge via usb and probably be fine.

But let's see how it goes. I haven't done it for a reason. While I think it's ok. I'm not betting on it without proper safety !!

 

[Ladiekali]

I just asked a friend this! Just peeking in.

 

[B2L]

Hey @Mooch just wondering if you have any preliminary findings yet?

Merry (almost) Christmas!

 

[Mooch]

Hey @Mooch just wondering if you have any preliminary findings yet?

Merry (almost) Christmas!

First results perhaps in a week.