Trickle Charger Question

[Eli]

Here's another one with much better specs:

Cellpro PowerLab 8

The idea is to cycle the sticks, noting capacity and measuring self-discharge. Discard the sticks with low capacity and/or high self discharge.

Here is a spreadsheet made by someone that bought two batteries, tested them and combined them to make one good pack.

https://docs.google.com/spreadsheet/...hl=en_US#gid=0

Remember, the operating word is balance. Good luck.

[Eli]

Originally Posted by E27006

We have used constant current 350mA power modules for the grid chargers.

There are some newer devices on the market, the constant current is controlable over a wide range say 35ma to 350mA

http://www.powerpax.co.uk/pics/pdf/p...012-04_dim.pdf

Also how about these modules:

DC input LED drivers

LED Drivers, Constant current

The miniature PCL 13510 is sold at Maplin for about £8

Constant Current LED Power Supply : High Power LEDs : Maplin Electronics

Ooh, neat. I like the variable one. Unfortunately the 30-350mA one only puts out 36V. It could still work though with the right setup.

The CC supplies we use are LED drivers.

[JohnVirginia]

Originally Posted by Eli

Here's another one with much better specs:

Cellpro PowerLab 8

The idea is to cycle the sticks, noting capacity and measuring self-discharge. Discard the sticks with low capacity and/or high self discharge.

Here is a spreadsheet made by someone that bought two batteries, tested them and combined them to make one good pack.

https://docs.google.com/spreadsheet/...hl=en_US#gid=0

Remember, the operating word is balance. Good luck.

I thought there was another concept of simply overcharging the ones with more capacity slowly with 350 milliamps (grid charging a total battery, not sticks) in order to force more charge in the low capacity cells/sticks (resulting in "better balance"). This is without replacing any sticks, i.e, rebuilding the battery.

If one does individual sticks from a disassembled battery (as being talked here) and overcharges them (I assume that is possible with the right charger setup) and possibly take readings to determine stop point, e.g., volts of the stick, temperature of stick?, and then cycling all sticks (charging/discharging/self discharging) several times one should end up with all the sticks having more capacity and thus "better" balanced when the battery is reinstalled. Of course, the reason to try this is because you don't have a $600 plus charger from Mike that does the whole battery. Having something else that can charge a stick of 6 cells that is available and significantly less expensive, albeit less safe for yourself and the car battery, gives options.

Don't all the batteries have some level of imbalance? Grid charging just keeps it from getting worse quicker. Doing this one time stick at a time charging (if it can cause the sticks to have more equal and higher capacity) seems like a viable alternative (just work to take the battery out and apart). Some of us work cheap you know.

[Eli]

Yes, that is correct, but it doesn't solve the actual problem. It's just a bandaid. By replacing the sticks with low capacity and/or high self discharge, you have effectively rebuilt the battery - removed the problem sticks.

If you were to just take the sticks out and cycle them, you would probably gain some temporary performance but the problems the battery pack is having would creep up again, whether it be from high self discharge or sticks with low capacity.

[Rush]

Originally Posted by Eli

Here's another one with much better specs:

Cellpro PowerLab 8

The idea is to cycle the sticks, noting capacity and measuring self-discharge. Discard the sticks with low capacity and/or high self discharge.

Here's one from the EV world BalancerLand - Home
At this link are actually 2 things, 1) A battery Balancer and also 2) a Battery Cycler - a charger/Discharger. The Balancer is quite complicated and not really for our needs, but the Cycler might be helpful for someone.

Parts are less than $40, but you have to build it yourself... and make the CB.

And one from the EV world that can monitor up to 13 batteries with a bar graph. It is set for 12v batteries, but I'm sure it can be easliy changed to measure 10 sticks of 14.4v, or 20 sticks of 7.2v
BATTERY MONITOR

[Eli]

Originally Posted by Rush

Here's one from the EV world BalancerLand - Home
At this link are actually 2 things, 1) A battery Balancer and also 2) a Battery Cycler - a charger/Discharger. The Balancer is quite complicated and not really for our needs, but the Cycler might be helpful for someone.

Parts are less than $40, but you have to build it yourself... and make the CB.

And one from the EV world that can monitor up to 13 batteries with a bar graph. It is set for 12v batteries, but I'm sure it can be easliy changed to measure 10 sticks of 14.4v, or 20 sticks of 7.2v
BATTERY MONITOR

Oh, believe me.. I've been all over that page, and quite a few like it.

The tap voltage monitor that a friend and I are developing will have "off" current draw in the single digit nanoamps. We did not think that the excessive draw of resistor solutions, despite the simplicity, was worth it when self discharge is such a concern for our packs.