Rechargeable lead-acid battery question

[Madmax908]

I have two things that use batteries, that are no longer holding a charge.

The first is the SLH100P HID flashlight.
http://tbn1.google.com/images?q=tbn...rechargeable-flashlights/vectorslh100p-ya.jpg

It uses a SW1270 battery rated at 12v/7.0Ah

The second item is the Back-UPS 300.
Listed here: http://www.apc.com/resource/include/techspec_index.cfm?base_sku=BK300C&ISOCountryCode=us
http://www.apc.com/resource/images/products/200/bk300c_b_v_200x100.jpg

The side of the battery has specs listed as 12v,7.2Ah/20R or replacement battery RBC2.

Both of these batteries are very similar. The dimensions and terminals are identical. I would say they are the same if not for the .2Ah difference listed on the side of the battery.


Can I order the cheaper (by about half) RBC2 that comes in the UPS, and put it in my SLH100P HID flashlight?

While I'm at it, anyone know if ther is another identical size battery with more capacity?

 

[rmteo]

The 12V/7AH SLA (sealed lead acid) battery is a common size that is used in emergency lights, UPS, etc. Typical dimensions are 151mm (5.95") x 65mm (2.56") x 94mm (3.70") and if it fits in your application, any one will do. Capacities for SLA's are pretty standard and in this size will be 7.0-7.5AH.

 

[Madmax908]

Thank you for the info and the quick reply!

 

[Kremer]

yep, same battery.

If you accidentally get the wrong terminal size for the POB it takes just a few minutes to crimp on the wider terminals to the POB wiring. Or you can bend the tabs up on the battery and use a file to skinny them down to fit, then bend back down. The APC without a doubt takes the larger 1/4" tabs.

 

[Madmax908]

I just got both batteries today from BatteryMart.
Like you said, I had to mod the terminals on the HID light.

I also ordered the recommended charger for the SLA batteries, but I'm confused.

The charger that comes with the HID has an output of 13.8v/ 750 mA.
The one from BatteryMart is 12v/1A. I bought it because it has a "float" function which won't overcharge and kill the battery (which got me into this situation in the first place).

Is the 12v charger going to be able to charge the 12v/7Ah batteries?

 

[Turbo Guy]

12 volts is the nonimal voltage for the charger just like 12V for the battery. Most 12 chargers in fact charge a 6cell PB to approx. 13.8-14.4 volts. A 1 amp. output charger should in theory take 7 hours to fully charge a completely depleated 7AH battery however for best life never completely discharge it. All PB batteries should be recharged as soon as practical after use. Try not to let them set discharged especially below 12.2 volts.

 

[Mr Happy]

I bought it because it has a "float" function which won't overcharge and kill the battery (which got me into this situation in the first place).

Actually it's very difficult to damage a lead acid battery by overcharging. As long as the battery doesn't vent or dry out it will happily take an overcharge forever. It is much easier to damage a lead acid battery by over discharging it -- for instance if the battery is running a light, make sure to recharge it long before the light fades or goes dim.

 

[Madmax908]

OK. I don't use the battery that often, but when I need it, I really need it to work. Should I just leave the charger on it all the time?

 

[Mr Happy]

OK. I don't use the battery that often, but when I need it, I really need it to work. Should I just leave the charger on it all the time?

A float charger should take care of that for you. You don't want an uncontrolled charge running all the time, but a regular top up charge or a controlled low maintenance charge would be perfect.

 

[VidPro]

. It is much easier to damage a lead acid battery by over discharging it -- .

or just by trying to use it more than 25 times :-)
for the price of shipping, disposal, length of use , and runtime , a ni-?? pack can replace a LeadWeight :-) so many times over its rediculous.
if your actually using it, vrses having it on emergency lights or a UPS or in a car or motorcycle.

 

[mdocod]

The float charger will greatly extend the life of the lead-acid battery.

Don't worry too much about the voltage/current rating on the charger than your spotlight came with. Technically speaking, that isn't even a charger, it's just a "wall-wort" transformer. Most cheap spotlights and devices that use a SLA battery in this fashion will just have a cheapo continuous trickle-charge via transformer with no real smarts to the operation. The addition of the float charger insures that the lead acid battery is kept in an ideal resting (but charged) state between uses, which will extend the useful life by quite a bit, years IMO.

 

[Turbo Guy]

or just by trying to use it more than 25 times

Oh so true but with qualifications.
I have a 12V / 12AH sealed AGM battery that was purchase 8-22-02 and it is still in near perfect as new condition. It gets topped off with $50 smart 1-1/2 amp. max. charge rate charger every 2-3 months. It never gets ran down more than 20%. I have several other 12V/7AH AGMs which are even older and they get similiar PM and are doing just fine.

Most of these sealed,mostly AGM batteries are designed for emergency standby useage not deep cycling. If you want one that can be discharged as during a power failure,recharged and used again and again purchase a Deep Cycle one designed for electric wheel chairs, scotters, round abouts and such. They cost a lot more but will last 200-500 cycles or so with decent care.

If you want the ultimate long life deep cycle,sealed 12V battery then....
purchase a quanity of DeWalt 36 volt cordless power tool packs from E Bay at approx. 100-$120 ea. each one has 10 ea. 2300 mAh A123 Systems LiFePO4 26650 size cells in them. Built a battery 4S xP( 4 cells in series and as many of tese in parallel as you need to reach required AH.) These can be discharged 100% hundreds and hundreds of time. They have extremely low self discharge so need topping of only once per year,have a 5 to 10 year shelf life and are as safe as any rechargeable high amp. out put battery can be.

 

[Madmax908]

Thank you everyone for the replies.

I have the float charger which will be pressed into use. :)