Lithium Ion battery packs 14.8 v??????

P

paul delany

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Hi folks I need advise here please.
I have searched Google for info on these battery packs, some use them with protective circuitry, while others just use them like the older Nimh battery packs, so what's the story please?? Can some one clear up my confusion please.
 
Paul, it appears that you are just starting to investigate battery power and there is a LOT to know before risking your expensive locomotive.

Just to address your confusion, it is probably because there are two types of Li-Ion cells; "unprotected" and "protected."

"Some" are using "unprotected cells" that are combined into a battery pack that contains a separate circuit board connected to all of the cells. Basically, you can buy preassembled "battery packs" made from "unprotected" cells that are usually held together with shrink tubing and contain circuitry that connects to all the cells and protects them from over/under charging or discharging and allows for the cells to be "balance charged", i.e. each cell is charged individually through a special charging connector. Many battery packs do not have the individual charging feature. You can buy "unprotected cells" and circuit boards to make your own packs, but it's a bit of a nuisance and could be dangerous. These battery packs are not intended to be disassembled.

The "others" are probably using individual "protected cells" and fitting them into a battery holder like you would individual NiCad or NiMh cells. With "protected cells" each cell has the protection circuit attached to the end of the cell and hidden in the cover, making it a little longer than an "unprotected" cell. The individual cells can be removed from the holder to be charged or there are chargers designed to charge four "protected" cells in series in a battery holder. Four individual Li-ion cells connected in series in a battery holder provide 14.8v nominal, but they are a little larger than standard AAA or AA cells and require a battery holder designed for them.

IMPORTANT: you CANNOT use an ordinary NiMh charger to charge Li-Ion batteries of any type. You MUST match the charger to the battery type and number of cells or you risk fire and explosion!!

Hopefully I haven't simply added to your confusion! There is a lot more to using battery power and several threads on this forum address the issues.
 
FatherMcD said:
Paul, it appears that you are just starting to investigate battery power and there is a LOT to know before risking your expensive locomotive.

Just to address your confusion, it is probably because there are two types of Li-Ion cells; "unprotected" and "protected."

"Some" are using "unprotected cells" that are combined into a battery pack that contains a separate circuit board connected to all of the cells. Basically, you can buy preassembled "battery packs" made from "unprotected" cells that are usually held together with shrink tubing and contain circuitry that connects to all the cells and protects them from over/under charging or discharging and allows for the cells to be "balance charged", i.e. each cell is charged individually through a special charging connector. Many battery packs do not have the individual charging feature. You can buy "unprotected cells" and circuit boards to make your own packs, but it's a bit of a nuisance and could be dangerous. These battery packs are not intended to be disassembled.

The "others" are probably using individual "protected cells" and fitting them into a battery holder like you would individual NiCad or NiMh cells. With "protected cells" each cell has the protection circuit attached to the end of the cell and hidden in the cover, making it a little longer than an "unprotected" cell. The individual cells can be removed from the holder to be charged or there are chargers designed to charge four "protected" cells in series in a battery holder. Four individual Li-ion cells connected in series in a battery holder provide 14.8v nominal, but they are a little larger than standard AAA or AA cells and require a battery holder designed for them.

IMPORTANT: you CANNOT use an ordinary NiMh charger to charge Li-Ion batteries of any type. You MUST match the charger to the battery type and number of cells or you risk fire and explosion!!

Hopefully I haven't simply added to your confusion! There is a lot more to using battery power and several threads on this forum address the issues.
Click to expand...
Probably the best advice about Li-ion batteries I've read. A balanced summary (took me ages to think of that pun)
 
Most Li-Ion packs I have seen come with BMS, and only have 2 wire, balance charging managed through the BMS, whereas Li-Po do not seem to have any BMS, and come with two SETS of wire, a pair for powering your motor, and a multiple set (number of sells +1) for balance charging.
 
FatherMcD said:
Paul, it appears that you are just starting to investigate battery power and there is a LOT to know before risking your expensive locomotive.

Just to address your confusion, it is probably because there are two types of Li-Ion cells; "unprotected" and "protected."

"Some" are using "unprotected cells" that are combined into a battery pack that contains a separate circuit board connected to all of the cells. Basically, you can buy preassembled "battery packs" made from "unprotected" cells that are usually held together with shrink tubing and contain circuitry that connects to all the cells and protects them from over/under charging or discharging and allows for the cells to be "balance charged", i.e. each cell is charged individually through a special charging connector. Many battery packs do not have the individual charging feature. You can buy "unprotected cells" and circuit boards to make your own packs, but it's a bit of a nuisance and could be dangerous. These battery packs are not intended to be disassembled.

The "others" are probably using individual "protected cells" and fitting them into a battery holder like you would individual NiCad or NiMh cells. With "protected cells" each cell has the protection circuit attached to the end of the cell and hidden in the cover, making it a little longer than an "unprotected" cell. The individual cells can be removed from the holder to be charged or there are chargers designed to charge four "protected" cells in series in a battery holder. Four individual Li-ion cells connected in series in a battery holder provide 14.8v nominal, but they are a little larger than standard AAA or AA cells and require a battery holder designed for them.

IMPORTANT: you CANNOT use an ordinary NiMh charger to charge Li-Ion batteries of any type. You MUST match the charger to the battery type and number of cells or you risk fire and explosion!!

Hopefully I haven't simply added to your confusion! There is a lot more to using battery power and several threads on this forum address the issues.
Click to expand...
Hi thankyou for your reply.
I'm still not clear though.
The packs I bought are 14.8v but have no ballance leads on them? And I see modelers using these packs all the time, what I don't understand is why the don't need a balancing pcb connected in the packaging.
 
paul delany said:
Hi thankyou for your reply.
I'm still not clear though.
The packs I bought are 14.8v but have no ballance leads on them? And I see modelers using these packs all the time, what I don't understand is why the don't need a balancing pcb connected in the packaging.
Click to expand...
How do you know there is no BMS in the packaging, they should be balanced charged from time to time.
 
paul delany said:
Hi thankyou for your reply.
I'm still not clear though.
The packs I bought are 14.8v but have no ballance leads on them? And I see modelers using these packs all the time, what I don't understand is why the don't need a balancing pcb connected in the packaging.
Click to expand...
Have you a make / model-number / link, you can post?

I hope you did not buy them from an electric fencing supplier on EvilBay?

PhilP
 
There is no obvious board on the pack, as you say..
There is very little information on the battery pack, and it is difficult to judge whether the individual cells have protection boards fitted, or not. - There is often a tell-tale 'step' at one end of the cells, if they are individually protected.

PhilP
 
There is a difference between a pack with an external connector for balanced charging/detection and a pack with an internal board connected for balance detection/protection and a pack with a single board internally with a simple under/over charge/voltage detector and a pack with nothing but batteries.

Takes a while to grok all the possibilities and pros and cons.

You just need to dig a bit, ask questions of the vendors.

Also you need to determine what you want. In my opinion, for our use, worrying about balanced charging is overkill, we don't beat up the batteries like the high performance guys do. Our discharge rate is 10 to 100 times less, and our quick charging requirements are less.

Greg
 
PhilP said:
There is no obvious board on the pack, as you say..
There is very little information on the battery pack, and it is difficult to judge whether the individual cells have protection boards fitted, or not. - There is often a tell-tale 'step' at one end of the cells, if they are individually protected.

PhilP
Click to expand...
Looking at the instructions on the pack (use only with original charger) I would hazard a guess that it is a replacement pack for some sort of device which most likely has a management board/software built in.
 
The latest Garden Rail to the rescue! See page 14... The author admits that he too was confused. Not a comprehensive guide, but useful information all the same.
 
Last edited:
FatherMcD said:
The latest Garden Rail to the rescue! See page 14... The author admits that he too was confused. Not a comprehensive guide, but useful information all the same.
Click to expand...
?
Confused?
?
My November Garden Rail, has an article about a tram conversion on page 14, and uses NiMH batteries.

PhilP
 
PhilP said:
?
Confused?
?
My November Garden Rail, has an article about a tram conversion on page 14, and uses NiMH batteries.

PhilP
Click to expand...
I have a digital subscription and received access to the December issue this morning. Didn't mean to cause confusion. :angel:
 
FatherMcD said:
I have a digital subscription and received access to the December issue this morning. Didn't mean to cause confusion. :angel:
Click to expand...
Although there was an article a couple of months ago in either the Garden Rail or 16mm Association magazines, I'll try and dig it out later
 
PhilP said:
?
Confused?
?
My November Garden Rail, has an article about a tram conversion on page 14, and uses NiMH batteries.

PhilP
Click to expand...
It's in the December edition.
Oops. I see that's already been said. Can't find the "Delete Post" button

Rik
 
GAP said:
Looking at the instructions on the pack (use only with original charger) I would hazard a guess that it is a replacement pack for some sort of device which most likely has a management board/software built in.
Click to expand...
I tried looking up the model number with Google. Looks like it's a replacement for the battery in a medical device. As you say, Graeme, it will probably have an inbuilt BMS board.

Rik
 
FatherMcD said:
Paul, it appears that you are just starting to investigate battery power and there is a LOT to know before risking your expensive locomotive.

Just to address your confusion, it is probably because there are two types of Li-Ion cells; "unprotected" and "protected."

"Some" are using "unprotected cells" that are combined into a battery pack that contains a separate circuit board connected to all of the cells. Basically, you can buy preassembled "battery packs" made from "unprotected" cells that are usually held together with shrink tubing and contain circuitry that connects to all the cells and protects them from over/under charging or discharging and allows for the cells to be "balance charged", i.e. each cell is charged individually through a special charging connector. Many battery packs do not have the individual charging feature. You can buy "unprotected cells" and circuit boards to make your own packs, but it's a bit of a nuisance and could be dangerous. These battery packs are not intended to be disassembled.

The "others" are probably using individual "protected cells" and fitting them into a battery holder like you would individual NiCad or NiMh cells. With "protected cells" each cell has the protection circuit attached to the end of the cell and hidden in the cover, making it a little longer than an "unprotected" cell. The individual cells can be removed from the holder to be charged or there are chargers designed to charge four "protected" cells in series in a battery holder. Four individual Li-ion cells connected in series in a battery holder provide 14.8v nominal, but they are a little larger than standard AAA or AA cells and require a battery holder designed for them.

IMPORTANT: you CANNOT use an ordinary NiMh charger to charge Li-Ion batteries of any type. You MUST match the charger to the battery type and number of cells or you risk fire and explosion!!

Hopefully I haven't simply added to your confusion! There is a lot more to using battery power and several threads on this forum address the issues.
Click to expand...
These have worked very well for me. Haven't gone wrong with tenergy. Two in series gives you the voltage. 4 in series parallel and they'll keep on going.
This is one of the two chargers I use.
 
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