Solar panel -> Lithium Ion Battery - WITHOUT controller - is it ok?

[Serj]

Hello all! ))

I have one question and if anyone give me answer - it`s a cool !!!

I`m a new member and i don`t know English language very well so sorry if my question already resolved ))

I have solar panel by PowerFilm - Rollable solar panel R28

http://www.powerfilmsolar.com/products/?r28&show=product&productID=271518&productCategoryIDs=6578,6580

Operating Voltage: 15.4
Wattage: 28
Current: 1.8 amps

and Li-Ion Rechargeable Battery Pack: 14.8V 13Ah (192 Wh)

http://www.batteryspace.com/li-ionboxbattery148v13ah192whwithcarlighterplugandsmartcharger.aspx

Voltage: 14.8V (working) 16.8V ( peak) 11.0V ( cut-off)

!!! Can i connect solar panel to battery pack WITHOUT any solar controller - its easy for me for everyday or i MUST use solar controller ?!

Thanks for you time ))

Best regards, Sergey

PS Sorry for my English, i`m just study

[Mike90250]

What does the battery manual say - are you allowed to charge from an un-regulated source ?

[inetdog]

What does the battery manual say - are you allowed to charge from an un-regulated source ?

My impression is that the system includes a Lithium battery charger designed to run off nominal 12 volt automotive power. So that may be OK if the panel voltages never get outside that upper limit. I am not confident in that.

[Serj]

What does the battery manual say - are you allowed to charge from an un-regulated source ?

Hello Mike! ))

About un-regulated source - nothing, absolutely nothing.
I send a same question to batteryspace and wait.

Have a nice day !!

[Serj]

My impression is that the system includes a Lithium battery charger designed to run off nominal 12 volt automotive power. So that may be OK if the panel voltages never get outside that upper limit. I am not confident in that.

Hello Inetdog! ))

...i am not confident in that, too

Have a nice day!!

[Serj]

Hello Mike! ))

About un-regulated source - nothing, absolutely nothing.
I send a same question to batteryspace and wait.

Have a nice day !!

Answer from batteryspace:

... We do recommend to have a solar charge controller to work with solar panel and Li-ion battery pack

[Sunking]

Here is the thing with Lithium battery charging. Lithium is different than lead acid batteries. They require a Constant Voltage method and solar is a very poor source for that. The charger has to be designed for the specific battery in question. For examle if you have say a 4.2 volt 10 AH battery, the charger should supply 4.6 volts @ 1 amp. When the current tapers off to .05 amps the charge is terminated.

It is obvious that will require a custom design using a significant over sized solar panel because current in a panel is unpredictable and you have to maintain at least 1 amp in this application for up to 10 hours (not going to happen with solar). The charger must maintain a very stable 4.6 volts and have the ability and smarts to monitor the current. Lithium batteries do not take kindly to over charging and cannot be floated like lead acid batteries. If you try to float a Lithium battery can result in explosion and fire.

[SunEagle]

Here is the thing with Lithium battery charging. Lithium is different than lead acid batteries. They require a Constant Voltage method and solar is a very poor source for that. The charger has to be designed for the specific battery in question. For examle if you have say a 4.2 volt 10 AH battery, the charger should supply 4.6 volts @ 1 amp. When the current tapers off to .05 amps the charge is terminated.

It is obvious that will require a custom design using a significant over sized solar panel because current in a panel is unpredictable and you have to maintain at least 1 amp in this application for up to 10 hours (not going to happen with solar). The charger must maintain a very stable 4.6 volts and have the ability and smarts to monitor the current. Lithium batteries do not take kindly to over charging and cannot be floated like lead acid batteries. If you try to float a Lithium battery can result in explosion and fire.

Also most Lithium batteries are multi celled which requires a smart balancing charger to make sure no cell gets over or under charged. These type of chargers are used by the Radio Control crowd like myself. I have over a dozen sizes of LiPo batteries and each one charges a little differently due to it's age and cycles of use.

You don't want to play with Lithium batteries unless you understand the end results (as Sunking mentions) can be more than just a dead battery.

[Sunking]

These type of chargers are used by the Radio Control crowd like myself.

Got a link to some of those LFP solar CC for RC. I know they exist.

[Serj]

Here is the thing with Lithium battery charging. Lithium is different than lead acid batteries. They require a Constant Voltage method and solar is a very poor source for that. The charger has to be designed for the specific battery in question. For examle if you have say a 4.2 volt 10 AH battery, the charger should supply 4.6 volts @ 1 amp. When the current tapers off to .05 amps the charge is terminated.

It is obvious that will require a custom design using a significant over sized solar panel because current in a panel is unpredictable and you have to maintain at least 1 amp in this application for up to 10 hours (not going to happen with solar). The charger must maintain a very stable 4.6 volts and have the ability and smarts to monitor the current. Lithium batteries do not take kindly to over charging and cannot be floated like lead acid batteries. If you try to float a Lithium battery can result in explosion and fire.

Hello Sunking! ))

Thanks you!!! I understand... i MUST use solar controller especially for 14.8V Li-Ion Battery Pack! Is it?

[Sunking]

Hello Sunking! ))

Thanks you!!! I understand... i MUST use solar controller especially for 14.8V Li-Ion Battery Pack! Is it?

You should use a controller for any battery type period. Th eissue you wil face is finding a controller for lithium.

[Serj]

Also most Lithium batteries are multi celled which requires a smart balancing charger to make sure no cell gets over or under charged. These type of chargers are used by the Radio Control crowd like myself. I have over a dozen sizes of LiPo batteries and each one charges a little differently due to it's age and cycles of use.

You don't want to play with Lithium batteries unless you understand the end results (as Sunking mentions) can be more than just a dead battery.

Hello SunEagle!

Thank you!!! I dont want it -

[Serj]

You should use a controller for any battery type period. Th eissue you wil face is finding a controller for lithium.

... like this http://www.batteryspace.com/mpptsola...tterypack.aspx

[SunEagle]

Got a link to some of those LFP solar CC for RC. I know they exist.

There are a lot of manufacturers like: Thunder power, Hitec, Duratrax, etc. I use a Revolectrix Multi4. What I like about it is the feature of giving you a true load % at the beginning and ending of each charge instead of just the voltage of the cells. It also has a number of different battery type charging features like LiFe so you aren't limited to LiPos.

Along with the charger you need to get a battery adapter to make the final connection to the battery balance charge plug. I use the CP4s-TP/PQ4S which can charge a 2, 3 or 4 cell battery. I also have a 120v to 12v adapter to run the charger off a house receptacle or I can use the 12 volt battery clamps and connect to my portable solar charging station.

Revolectrix makes bigger chargers and adapters for up to 10 cell (10s) batteries along with a lot of other RC type equipment including flight stabilization. I think they provide quality equipment for a pretty low price.

[Sunking]

There are a lot of manufacturers like: Thunder power, Hitec, Duratrax, etc. I use a Revolectrix Multi4. What I like about it is the feature of giving you a true load % at the beginning and ending of each charge instead of just the voltage of the cells. It also has a number of different battery type charging features like LiFe so you aren't limited to LiPos.

Along with the charger you need to get a battery adapter to make the final connection to the battery balance charge plug. I use the CP4s-TP/PQ4S which can charge a 2, 3 or 4 cell battery. I also have a 120v to 12v adapter to run the charger off a house receptacle or I can use the 12 volt battery clamps and connect to my portable solar charging station.

Revolectrix makes bigger chargers and adapters for up to 10 cell (10s) batteries along with a lot of other RC type equipment including flight stabilization. I think they provide quality equipment for a pretty low price.

OK help me out with some info that puzzles me. What is being referred too when they specify 1S, 2S, 3S... battery packs? Is that the number of parallel strings in the pack for AH? Or number of series cells for voltage?

I suspect Series voltage because of this spec.