Hi;
I am building a Robot chassis using old Power Chair Motors. The two 12v batteries from the power chair are very large and heavy.
Can anyone recommmend some smaller batteries to rplace these?
Not sure if there are any marnings on the motors .
I found a pic of one of the batteries - these are 12v 27AH.
This will depend on how much
This will depend on how much money you have to work with.
One suggestion is to re-use old laptop batteries. You can take them apart and there is LiPo batteries inside which depending on their condition will work. I have re-used many old laptop batteries this way and in most cases you will have one cell that is bad and will not hold a charge while the rest are still fairly good.
Another idea is to still use a lead acid battery but a smaller case which would be a lighter. Wal-Mart carries a battery in the sports section that is a 12v lead acid battery that is used in some of the hunters cams. I have found those great to use for small projects and they are less than $20 per battery.
And one last idea for you.
If you have an old tablet laying around they have inside a 3.7v 1800 to 2200 mah battery.
I think the laptop battery is going to be your best best as it will be light weight and be able to drive one motor.
Hope this helps you.
ditto on the laptop
ditto on the laptop batteries,
I’m using them on various projects atm, a good power to weight ratio. try getting old packs from a local independent PC repair shop, no doubt it will be a problem for them to get rid of so might be free.
make sure you combine in parallel to get enough discharge rating, as the cells in laptop batteries (they are called 18650 cells) normally only do 1 x their capacity, and make sure you check their capacity before you make a pack up with them. there is loads of info on the net about it, just google for the 18650 cell.
I made a cell pack for a new robot, its got a total of 40 cells giving out 18 amps and 21 volts, weighs in just over 2kg
Regards
Alex
I’ve been using power tool
I’ve been using power tool LiPo batteries a lot lately. Lowes has a Kobalt 24v 1.5Ah battery for a mere $10, and it has a little voltage level checker built in. I designed a 3d print object that includes V+ and V- terminal screws, and I print one for just about every robot thing I build. I bought several of the batteries and their charger, all for less than $100. I get 24v-5v DC converters on Amazon for under $10, and that gets power supplied to arduinos and raspberry pis. I get 10a 24v-12v DC converters for around $15, and that gets power supplied to motors (that can’t handle the full 24v).
Here’s the battery I’ve been buying: https://www.lowes.com/pd/Kobalt-24-Volt-1-5-Amp-Hours-Lithium-Power-Tool-Battery/1000090833
The charger: https://www.lowes.com/pd/Kobalt-24-Volt-Max-Power-Tool-Battery-Charger/1000102901
My 3d printed object: http://www.thingiverse.com/thing:2304440
The things I hack up for the terminals: https://www.lowes.com/pd/AMERICAN-VALVE-1-2-in-to-1-2-in-dia-Copper-Plated-Steel-Milford-Hanger/3223453
The screw inserts I use to hold the screws (Screw-to_expand inserts for Through Holes in Plastics - 6-32): https://www.mcmaster.com/#catalog/123/3328/=17jdfht
I’ve been meaning to write up a blog post about this, thinking it might really come in handy for someone else. It sure has solved my battery problems lately.
