Andymark How Do I

Batteries are connected to the breaker and PDH through an SB50 Anderson connector. This connector is usually purchased from andymark precrimped.

The battery cable from andymark does not come with the lugs. However, these can be found pretty easily in packs. There is a bag in the orange box labeled power components or batteries I think. This will need to be crimped onto the battery cable.

If you purchased batteries through an FRC vendor, it typically comes with the associated hardware to attach the cables to the terminals. These are small 10-32 bolts, washers, and nuts that hold the terminals to the lugs on the cable. You will want to avoid stripping the bolts by overtorquing, but also, torque enough such that the cable cannot move or rotate when tugged adequately by hand.

After the cables are attached to the terminals, you will need to electrically insulate the exposed metal parts. Prior to attaching the cables, you should slide a length of heat shrink onto both cables. Then, you can apply the heat shrink with the heat gun, and cover the remaining bits with electrical tape.

Battery quality is measured at the basic level by two things: peak voltage and internal resistance. Healthy batteries will have a high peak voltage and lower internal resistance than an old or degraded battery. These two numbers can give an idea of how much power or energy is actually stored and being discharged by the battery.

However, they do not give the complete picture. Other things like voltage sag are important to determining when a battery is healthy and can be used for competition and when they should be retired. The inital battery voltage often measured using a battery beak will be inflated due to surface charge that will quickly dip. The battery will reach a stable voltage where it will then slowly fall as it is used. Once the battery has been discharged towards its limit, the voltage will fall quickly again. This curve is what more advanced battery testers will reveal.

We don't have the testing equipment to examine batteries to that level, so its mostly just keeping track of how long batteries run for and if brownouts occur.

If you notice that a battery is losing voltage faster than normal, that battery is likely to be old and worn. Additionally, the inital battery voltage doesn't matter much, where it stays for the first 2.5 minutes of testing is what's important.

Sealed Lead Acid batteries like the ones we use in FRC will degrade over time. They can also fail due to a variety of things like cracking the seal and releasing gases. They should ideally be stored at room temperature if possible and kept plugged in to drip charge. These two factors are the main things when a battery degrades over time.

Batteries should idealy be carried by both hands and handled gently. They are very heavy so carrying them by their cables can damage the cables and the connectors leading to failure during compeititon and may lead to the cables falling off. Dropped batteries are a hazard to bodies, feet, and chemical reactions. Batteries may start leaking acid if the casing becomes cracked. This is more likely to happen after dropping a battery on the ground.

Leaked battery acid is acidic, so a base like baking soda can neutralize it. It is important to stay calm in the event of a chemical spill, wiping off the acid and washing it with soap and water are likely to be enough to prevent any bodily harm from acid.

We want to do this with the ~20 dead batteries sitting on our shelf, but we haven't gotten around to it yet.