When getting a external battery to run a robot, do you want a "deep cycle" or "regular" battery? I can't quite rap my head around which one would be better.
DEEP CYCLE
It has thicker plates and bigger spaces between them so it can discharge more times.
"Regular" or starting batteries are optimized to deliver high power for a short time but to rarely get significantly discharged
Deep Cycle all the way.
A Deep Cycle Battery (by definition) is designed to be discharged farther (deeper), and recharged (faster), than a standard battery designed to be used in say an automobile or even a boat. It will handle this "deep cycling" routine better (and longer) than a standard battery.
Loyal
If you run long sessions between charging the deep cycle will probably be better.
Regular lead acid batteries get unhappy if you regularly pull them down to below half-charge. They are better for heavy loads of short duration, like vehicle starting
And be sure to get a Gel Cell type battery, they will not spill, even if turned upside down!
Deep cycle will give better long term performance. Regular batteries tend to fail prematurely if they are completely discharged prior to charging.
Too heavy, I am converting all of my old robots to LiPo and getting about three days out of a battery that is very light and easily fits in a vest.
Thanks for the help.
Lipos have kind of a bad reputation in the R/C world for catching on fire. I think it was also LiPos that grounded the Boeing Dream Liner after smoking up some cabins. So, be careful with those. I'm not sure it's worth the risk.
Well aware of that, but, we are talking about pack of three battery cells connected in series to one balance charger. You could wire them through a balance charging board inside the battery case if it were that big of a concern and completely eliminate the issue. If you did that you could run a cheaper charger too.
A car or a plane have very complicated arrays to balance the cells so that one does not over charge. A modern balance charger can do that as long as YOU do not connect it to an array yourself. I tried, just to see what it would do. I set it at 1 amp charge rate and the charger could not figure out the cell count so it would only charge at 0.1 amp
I have "let the crew's" at them and only one issue so far. One guy managed to connect it completely backwards, to my amazement, set it to charge and went home. It had to be beeping at him, LOL. The charger knew it was FUBAR and shut down, never going to charge mode just like it was supposed too.
I started into LiPo very tentatively as I had the same concerns as you. I am very happy with them right now
Deep Cycle
we have a couple deep cycle absorbent glass mat (AGM) batteries used for wheelchairs, they usually are 35-40ah and don't last quite as long as the 12 volt Optima, but last a full day.
The Optima is expensive, and being heavy it doesn't get used unless the base is accessible by driving right to it.
> Well aware of that, but, we are talking about pack of three battery cells connected in series to one balance charger. You could wire them through a balance charging board inside the battery case if it were that big of a concern and completely eliminate the issue. If you did that you could run a cheaper charger too.
>
> A car or a plane have very complicated arrays to balance the cells so that one does not over charge. A modern balance charger can do that as long as YOU do not connect it to an array yourself. I tried, just to see what it would do. I set it at 1 amp charge rate and the charger could not figure out the cell count so it would only charge at 0.1 amp
>
> I have "let the crew's" at them and only one issue so far. One guy managed to connect it completely backwards, to my amazement, set it to charge and went home. It had to be beeping at him, LOL. The charger knew it was FUBAR and shut down, never going to charge mode just like it was supposed too.
>
> I started into LiPo very tentatively as I had the same concerns as you. I am very happy with them right now
Always love to hear first hand accounts. Thanks for posting!
I use a booster pack made for jumpstarting cars. It has a 12 18ah sealed lead acid battery that I have replaced once in the last 10 years. I don't use it everyday like most people would.
Tempted to try a motorcycle/atv battery from walmart next time I need a battery. They have them on the shelf now that are AGM.
James
That is what I use.
Since I don't use it every day, it can be useful elsewhere too.
They come with usb charging ports, lights, airpumps and they will jump start a vehicle.
The first reason I chose the booster pack was because it had a handle.
B-)
Deep cycle is the best, hands down.
But, I have found that the warranty on Deep Cycle batteries is typically 1-year and the warranty on 'regular' batteries can be as long as 5-years.
The regular battery that I have, has been replaced under warranty twice by Walmart. I don't have enough time on my current deep cycle battery (it is 18-months old) to form a life expectancy estimate.
So while I know the Deep Cycle is best, I wonder if the regular battery (which costs less initially) might be better in the long run if you get a new one every year.
It seems to me that the manufacturer is making an interesting equation with the shorter warranty.
M
The warranty may not be any longer on deep cell but I've got one in my camper that is 8 years old, has been completely "dead" at least 4 times and is still going strong. I do recharge it with a trickle charger about once a month during the winter when I'm not camping though.
Andy
LiFePO4
I've been using these:
http://www.batteryspace.com/lifepo418650battery128v4050mah5184wh7aratewpcb.aspx
for 2 years now & they're just starting to show a slight drop in voltage when fully charged. One runs my robot and associated 900 Mhz 0.5 watt modem all day.
2-3 times pricier than SLA batteries, but 1/3 as heavy and supposedly good for >2000 charge/discharge cycles. You need to use their charger, as well.
SS
We use those as well, the handle just makes it easier to carry. Which helps where you have a hike from the truck.
LiFePO4
Interesting option. Have you tested what is the usable amperage that you are getting out of the battery? Looks like it should be 4.5 amp or just over a long day of hard use. I went with these http://tinyurl.com/l7w2nda as is covered in another thread and we are getting a usable 9.5 amps @ 636 grams. The pack you are using states 545 grams and with a printed case of +/- 45 grams or 590 grams total. Your amp per gram is no where near as good, but, the voltage is closer to what the equipment wants and you don't have to listen to the "low battery" chirping.
I am guessing you seen no issues with the static voltage being just a bit too high? I can't imaging that you would as NiCD could get quite high when new and that is what a lot of this was designed for
LiFePO4
I've been using ENIX 15V 7ah LiONs since 2008. I made three up then and they are still performing as new. ANSMANN do a similar cell. I used a suitable ABS box to hold the pack, fuse and connector socket - fits in my jacket pocket.
The overheating problems with this type of battery appears to happen only when multiple cells are made up without control circuitry. If you buy them as a manufacturer's pack there should be no problem, as long as you use the manufacturer's charger.
They are much more expensive then normal batteries/chargers, but they hold charge and performance forever, so long term it's money well invested. AND they are lightweight - you could carry 30aH with you in jacket pockets if you wanted to.
Only point to note is that instrument "low battery" warnings are not tuned to these batteries, so there may only be a couple of minutes warning of lack of voltage.
LiFePO4
Jim and I use a garden tractor battery up in Nome. Runs the base for 3-4 days before needing recharging. Small and light enough, I can pick it up with one hand. Been using the same one for 4 years now.
-JD-
